CHANCELLOR George Osborne has claimed that the global economic crisis has reached a "dangerous phase" but also hailed progress in agreeing emergency action.

He said finance ministers were “optimistic that we have taken a step towards resolving it” following crunch talks in Washington DC.

International Monetary Fund (IMF) officials said they had been encouraged by the willingness of eurozone governments to do what was necessary.

They said the situation remained “precarious” but noted a “very clear recognition by ministers of the gravity of the situation we are in”.

Speaking after the talks, Osborne said: “I think there is a recognition here that the debt crisis has reached a dangerous phase. But we are optimistic that we have taken a step towards resolving it.

“The countries of the eurozone, which are at the epicentre of this crisis, understand that they need to take decisive action.”

The Chancellor previously said that eurozone countries had just six weeks to devise a long-promised solution to the crippling debt crisis, suggesting a meeting of the G20 nations in France in November was the deadline for action.

He insisted no specific plan had been put forward to deal with a Greek default, amid reports that G20 ministers had privately accepted that it was likely to happen.

“No-one here has put forward a plan for a Greek default,” he said. “Greece has its programme. It’s got to meet its conditions but it is also clear that the eurozone has to deal decisively with their issues.

“At this meeting we have seen the eurozone understand that they are at the epicentre of this global debt crisis, that it has entered a dangerous new phase and that the sooner we resolve it the better for the whole global economy.”

IMF managing director Christine Lagarde said there had been a “common diagnosis and a shared sense of common purpose” without “finger pointing” at the talks.

She added that while the situation remained “grave”, the global economy was “half-way through the work that needs to be done”.

A late rally on Friday was not sufficient to prevent the FTSE 100 suffering its second worst weekly fall this year, losing 5.65%, or £78 billion, from its value.

Turmoil continued on markets across the globe as world leaders failed to ease global recession fears sparked by a gloomy outlook from America’s central bank, weak Chinese and eurozone economic data, and the enduring sovereign debt crisis.