Sajid Javid said he did not think nationalisation was the solution to the crisis but it "wouldn't be prudent to rule anything out" to clinch a deal.

He said any buyer would want to look at "plant, pensions and power supply" - which ministers were "working on".

Labour said nationalisation should be considered until a buyer is found.

It comes after Tata Steel announced it was selling its loss-making UK business, which employ thousands of workers across plants in Port Talbot, Rotherham, Corbyn and Shotton.

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In an effort to help save the industry, the government has said that public sector bodies will be encouraged to buy British steel for construction projects.

But the Local Government Association told the BBC that councils were already considering local economic and social factors when awarding contracts.

Speaking on BBC One's Andrew Marr show, the business secretary - whose handling of the crisis has been criticised by opposition parties and unions - said the UK steel industry was vital for economic and national security.

"I don't want to live in a country where we have to import all our steel, and we will do everything we can to support the industry," he said.

He said the government's plan to save the plant and find a long-term solution for the steel industry was to find a commercial buyer for all of Tata's UK business.

Tata had accepted that finalising any deal would take time, he said.

"The UK government knows, I've know for a while, that we're going to also have to offer support to eventually clinch that buyer and to give this steel plant a long-term viable future," he said.

Mr Javid said any buyer would want "to look at what I have referred to internally as the 'three p's' - plant, pensions and... power supply".

He added: "These are the kind of things we've already thought, we've already started working on, and what I hope is that you will have the offer document from Tata, overlay on top of that the help the British government can provide, then you have the makings of a successful deal."

Mr Javid said the government "will look at everything we can do to allow a sale going ahead. I wouldn't rule out anything at this stage".

But asked to guarantee that the plant would stay open, he did not, saying: "I will do everything I can to keep this plant open."

Labour is calling for the industry to be temporarily nationalised, with shadow chancellor John McDonnell suggesting the government could maintain a stake in the plant after a buyer was found.

But Mr Javid told the Marr show that nationalisation was "rarely the answer".

Guidelines were introduced last year requiring central government bodies to take into account the "true value" of British steel.

Now the guidance is to be extended across the public sector and public procurements involving the supply of steel will need to consider "responsible sourcing, the training suppliers give to their workforce, carbon footprint, protecting the health and safety of staff and the social integration of disadvantaged workers".

Contractors working for the public sector will also be required to advertise their requirements for steel so that UK firms can compete for the business.

It comes after heavy criticism of ministers for failing to take more effective action to prevent the "dumping" of cheap Chinese steel, seen as one of the key reasons for the problems in the UK steel industry.

The unions said it was "a small step in the right direction" but the measure should have been in place already.

The government has played down the impact of new Chinese import tariffs of up to 46.3%.

Roy Rickhuss, general secretary of the Community trade union, said the announcement was "a small step in the right direction" but said steelworkers "will be shocked to discover that these measures were not already in place".

Tony Burke, assistant general secretary of the Unite union, said the measure needed to compel British steel to be used in all infrastructure projects "otherwise, there will be no recognisable steel industry left in the UK to benefit".

Shadow business secretary Angela Eagle said while the announcement was welcome, ministers had been dragged "kicking and screaming to take action" and needed to do more if they were to ensure the survival of the steel industry in the UK.

Meanwhile, First Minister Carwyn Jones called on the Westminster government to give the industry the same support given to banks during the financial crisis.

Writing in The Independent, Mr Jones said there was "a moral, economic and strategic case" to do the same for steel.

A possible buyer has emerged for the Port Talbot steelworks in south Wales.

Steel tycoon Sanjeev Gupta, founder of the commodities firm Liberty House, said he had already opened discussions with Tata Steel and was ready to hold talks with the government.

"We would need a proper partnership with the government. I don't know what that would entail at this stage. We've started the discussions... we are in the process of starting a discussion with Tata," he told The Sunday Telegraph.

He added: "I haven't made a proposition that I want to buy all of [Tata Steel UK] because that's too big an undertaking to even put on the table at this stage."

"If the company, its people, its workers and the government would be willing to consider my suggestions then I'm willing to engage in a discussion about what role we will play in that."

Tata's UK business - which directly employs 15,000 workers and supports thousands of others - includes plants in Port Talbot, Rotherham, Corby and Shotton.

Steel production makes up 1% of Britain's manufacturing output and 0.1% of the country's economic output.

The Department for Transport used to take random cars off the road and then test the levels of dangerous gases coming from the exhaust pipe.

But a Freedom of Information request for the BBC shows that the spot-check scheme was dropped in 2011.

That left the carmakers to police themselves.

The chair of the Transport Select Committee, Louise Ellman, has called the news "deeply disturbing".

The committee is currently investigating vehicle emissions after VW admitted cheating pollution tests in the US.

"I will be pursuing both the VCA (Vehicle Certification Agency) and the Department for Transport on how this happened when they appear in front of the committee as part of our ongoing enquiry," said Ms Ellman.

However, the government has not broken any rules.

EU regulations only oblige carmakers to test their own vehicles. Manufacturers hand their results over to the relevant type-approval authority, but it would appear no-one independent sits in the lab, double-checking what's going on.

Although the UK government has stopped double-checking ordinary cars, some other governments still do it.

The Swedes and the Germans both have a programme. The Americans also spot-check cars based on a number of criteria. Sometimes they pick a model at random. They also select vehicles based on the manufacturer's data and on inquiries and complaints from the public.

John German is one of the key people who helped catch VW cheating. He is from a group called the International Council on Clean Transportation (ICCT) and he told me that the latest available figures show spot-checks had some effect in the US.

"Based upon this in-use testing, as well as defect reports, there were 42 voluntary and mandatory emission-related recalls in 2009, 39 in 2010 and 53 in 2011," he said.

Meanwhile, his colleague Peter Mock said he was "convinced that it is very important for governments to carry out vehicle tests".

"Even though of course the testing itself is only one part of it," he adds. "The other part is to ensure that the vehicles chosen for testing are representative and not specially prepared, that the testing is carried out under realistic conditions, and that anything suspicious found would trigger thorough investigations and ultimately also penalties."

The UK government argues that it unearthed only two problems in a decade, and that taxpayers' cash was better spent elsewhere.

"Manufacturers have always been required to conduct 'in-service' testing to ensure their vehicles continue to meet regulations," a spokesman told the BBC.

"The Vehicle Certification Agency (VCA) previously conducted additional testing on top of this, but a decision was taken in 2011 to divert resources to improving our understanding of the effect after-market alterations are having on vehicle emissions."

In other words, they stopped checking normal road cars and moved to an important, but more specialist area, vehicles that had been "chipped" by customers. That's where the software is changed to improve performance.

They changed tack and they also cut the budget. It used to be about £200,000 a year. Last year, they spent just £42,300.

"We are fully committed to improving air quality and have led calls at a European level for Real Driving Emissions testing that will mean all new cars have to adhere to robust real-world standards from as early as next year," the government spokesman added.

So, what is 'in-service' testing?

The rules say that older cars must still pass an official, European emissions lab test. It's there to protect public health, because scientists estimate that pollutants from cars kill tens of thousands of British people each year.

Manufacturers have to double-check their own vehicles and pass on the results to the government, whose experts can order more tests if they suspect a problem.

Since 2005, government inspectors tested around 10 different models per year. Details seen by the BBC show they checked a number of VW and Skoda diesels in that time.

Some of those cars could potentially have been fitted with a defeat device, although don't forget it was well hidden in the computer, and inspectors were not allowed to look at computer software.

Between 2005-06 and 2010-11, 227 individual tests were completed (76 petrol and 151 diesel) and 87 vehicles failed to achieve a "pass" for all pollutants (14 petrol and 73 diesel). When cars failed, they carried out more tests.

Overall, the government says there were just two model failures in a decade, a Mitsubishi Carisma Petrol, (2005-06 test) and a BMW Mini One D (2008-09 test).

In the case of the BMW Mini, the government says that the German approval authority (KBA) was told "to enable them to take action". It does not say what that action was, if any.

And with the Mitsubishi, the manufacturer was contacted directly and they found "a number of anomalies in the test vehicle that could account for the failed result".

After further talks with the manufacturer, "no further action was taken".

In a decade, the Driver and Vehicle Standards Agency has never taken action against a car maker because of "in-service" testing.

Testing has re-started again.

After the VW scandal, the UK government actually began car spot-checks again. The BBC was invited to see them in action.

But it's a one-off programme and it will stop in the spring.

No one was hurt after the roof collapsed at Rumworth School in Bolton at about 16:30 GMT on Saturday, Greater Manchester Fire Service said.

North West Ambulance tweeted that many cars and fences were damaged when debris with "dangerously sharp edges" spread over a large area.

They said it was a "lucky escape" the incident happened during the Easter weekend when no one was at the school.

The school said on its website it was "confident" that it would still re-open on 4 April at the start of the new term.

West Yorkshire Police said the bodies - believed to be two women and a man - were found in the East End Park area of the city after officers were called shortly before midday.

The force said there appeared to have been a small fire at the property.

Acting Detective Inspector Mark Atkinson said: "We believe the deaths are likely to have occurred in the early hours of Saturday".

He said: "We would like to hear from anyone who has seen the occupants of the address on Friday."

A cordon is in place at the address in East Park Street and police remain at the scene.

Post-mortem examinations are due to be carried out to establish a cause of death, the force said.

Lord King told the BBC the euro area of 19 EU countries would continue to be the UK's biggest trading partner.

Leave campaigners argue the UK could strike better deals with faster-growing countries if it were outside the EU.

However, Germany's finance minister warned the world economy would be "poisoned" if the UK departed.

British voters will be asked whether the UK should remain an EU member in a referendum on Thursday 23 June.

Asked if the UK would be badly affected by eurozone troubles after the referendum, Lord King told the Andrew Marr Show: "That will be true, in or out."

The life peer was governor of the UK's central bank during the financial crisis and stepped down in 2013.

He said the euro project had been a "mistake" and that Germany, one of the driving forces behind the single currency, could be better off leaving.

"That is why in the longer run the euro area, not the EU but the euro area, is something that we should all be concerned about," he said.

He would not comment on whether he was in favour of the UK leaving the European Union.

The UK sold £200.4bn of exports to eurozone countries in 2014, which was 39% of all the goods and services it sold abroad that year, according to the Office for National Statistics.

Campaigners on both sides of the EU referendum are focusing on how the vote will affect British trade.

Speaking on the same show, London Mayor Boris Johnson said the "riskier option" was to stay inside the EU because its focus was on preserving the eurozone.

German finance minister Wolfgang Schaeuble conceded that the UK could negotiate a new trade deal to stay inside the single market - a free trade zone across all 28 EU countries - without being a member of the EU.

However, he said, a UK decision to leave would cause "years of the most difficult negotiations".

"For years we would have such insecurity it would be a poison to the economy in the UK, the European continent and the global economy as well," Mr Schaeuble said on the show.