DAVID Cameron has agreed to fund a £20 billion high-speed rail link between Scotland and London that would cut the journey time to three hours if he becomes prime minister.

A Conservative government would fund the southern leg of the route with the Scottish government taking responsibility for funding the remaining length of track from the border to Glasgow.

The scheme would cut journey times by using TGV-style double-decker trains that would offer a quick and greener alternative to air travel.

The new route would provide a link between Scotland and Europe, allowing passengers to travel between Glasgow and Paris in just over five hours.

Alex Salmond has already committed his government to funding such a proposal — a key element of the Sunday Times Get Scotland Moving campaign, launched last year.

Cameron has instructed David Mundell, the shadow Scottish secretary, to begin talks with the first minister to agree a timescale for the launch of the proposal soon after the next general election, expected to be in 2010.

The Conservative leader believes the link is necessary to boost economic growth and cut pollution by reducing the need for internal flights.

Cameron also sees it as an early opportunity to demonstrate how a Tory government can work positively with the SNP despite Salmond’s proposal for an early referendum on independence.

Last month a YouGov poll for the Sunday Times found that 25% of those Scots who oppose independence would be more likely to vote for it if Cameron wins the next election, a finding that has alarmed senior Tory strategists.

Mundell said: “The fundamental difference between the SNP and the Conservative party is not about left or right, it is that we want to do things for Scotland within Britain and they want to do things for Scotland outside of Britain.

“But there is no reason why some of those things should not be the same things. The real benefit of David Cameron as prime minister for devolution is that he does not have any of the pre-devolution baggage that Labour has, he doesn’t look at how it was pre-1999 but looks at how we can make things work most effectively.”

Mundell added: “The high-speed rail link to Scotland is a good example of how the two governments could work together and we’re committed to doing it.

“We are very supportive of the idea and very keen to hold early talks with the Scottish government to see how it can be delivered.

“It’s quite clear that the economy and the environment of Scotland would benefit from having the sort of high-speed rail links that we see elsewhere in Europe.

“It’s not just about cutting a considerable amount of time off rail journeys but it would allow the number of internal flights between Scotland and London to be reduced for the good of the environment.

“If the rail link were just to stop at the border it wouldn’t be of any benefit.”

Cameron expects the Scottish government to make a contribution to the cost of the project, which could account for 10% of the funding, covering the cost of new track that would need to be built in Scotland.

Scottish government ministers fear Scotland risks being left behind after the recent opening of the new St Pancras International station, which has cut the journey time between London and Paris to 2 hours and 15 minutes.

The SNP fears that without better links from Scotland the new Eurostar service will harm the Scottish government’s chances of meeting its target of a 50% rise in tourism by 2015.

A spokesman for Stewart Stevenson, the transport minister, said: “This is what we would expect of any government at Westminster, and we welcome any recognition of Scotland’s interest in high-speed rail links.”

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