The CBI has said that an extra £70 billion of investment is needed over the next decade to improve Britain's ailing transport infrastructure.

According to the business lobby group, government plans for around £180 billion of public and private spending will not prove sufficient.

CBI chief Digby Jones warned that business patience and public tolerance "is becoming exhausted by the slow pace of improvements".

The level of spending set out in the government's 10 year transport plan is the "minimum required to make acceptable progress", the lobby group warned.

Delivering a transport system to rival the best in Europe remains a dim prospect and would cost a great deal more, it added.

In the short term, ministers were urged to increase transport investment by an extra £2.7 billion between 2005 and 2008, the three financial years covered by the current public spending review.

But over the longer term, the CBI said a "significant step-change" in investment is needed, with an additional £21 billion required during the three financial years between 2008 and 2011 and a further £100 billion needed overall between 2011 and 2015.

On roads, there was a call for the widening of the M1, M6 and M25.

And there was backing for a quick decision in favour of London's Crossrail project.

"We have a first rate economy and it deserves a first rate transport system, not the substandard infrastructure that is currently letting down the whole country," said Jones.

"The original 10 Year Plan was full of promise but four years and £50 billion later there remain profound deficiencies in the UK transport system.

"The catalogue of transport nightmares gets ever longer."

Jones added that the current plan has "clearly stalled" and warned against any further mistakes or delays.

"Our call today is for a major step-change in the speed of improvement and level of funding dedicated to the transformation of the UK's transport system," he said.

"The country is crying out for it and there can be no more excuses."