Mr Rudd, who left Australia this afternoon for the summit in Washington, dismissed suggestions the group's membership was too big and unwieldy to produce any effective strategies.

"I believe China and India do deserve a greater place at the international table," Mr Rudd today told ABC Television in his only pre-departure interview.

"One of the ways in which that can be secured is through the continuation of the G20 into the future."

That would depend in part on how Friday and Saturday's meeting is managed.

If it was a success, Mr Rudd said the G20 could continue as a vehicle to deal with longer-term challenges and include the major emerging economies of China, India, Brazil, Mexico and possibly others such as Indonesia.

The meeting will examine ways to stem the crisis that has started eating away at the real economy, and put the brakes on global growth.

But the mammoth task of finding a circuit breaker to the turmoil was evident as world markets again headed south, spooked by changes to the $US700 billion Unites States government rescue strategy.

Negative global market sentiment worsened after US Treasury Secretary Henry Paulson scrapped plans to buy toxic mortgage securities in a refocus of the government's massive financial rescue plan, raising fears the US economy may be deteriorating rapidly.

Few nations have been spared the pain as the steamrolling credit turmoil has jumped from financial markets and begun to impact jobs, growth and business confidence, leading some to speculate the world is heading for its worst slowdown since the Great Depression.

US President George W Bush will host the G20 summit of developed and developing countries on Saturday, but the man who will lead America for the next four years, president-elect Barack Obama, will not be there.

Mr Rudd arrives in Washington this evening and will join Treasurer Wayne Swan, who has been holding meetings in New York and the US capital over recent days.

The prime minister will have a series of bilateral meetings with other world leaders as well as financial and economic decision makers tomorrow before sitting down at the G20 forum with international counterparts including Britain's Gordon Brown, France's Nicolas Sarkozy, China's Hu Jintao and Japan's Taro Aso.

Mr Swan told CNN International any response to the financial crisis required coordinated global action.

"Action when it comes to strengthening the economy through fiscal policy and monetary policy, and also action when it comes to strengthening financial systems," he said.

"And also a plan for the future in terms of resolving the problems that caused this crisis and putting in place reform for the future."

Many countries have begun pump priming their economies, including Australia with its $10.4 billion economic stimulus package, targeting aged pensioners, families with children and the housing market.

The US is looking to re-target its $US700 billion bailout package, putting more money into frozen credit markets, making it easier for Americans to access consumer finance, while Beijing will attempt to stimulate the massive Chinese economy with a package worth nearly $US600 billion ($A940 billion).

And just as there's been coordinated action across the globe to cut interest rates in response to the financial crisis, Mr Swan is calling for similar action on fiscal policy.

"I do believe there is common ground when it comes to the need for fiscal policy action," he said.

"You've seen coordinated action from time to time when it comes to monetary policy.

"And I do believe we can find the consensus in terms of the reform of the international financial architecture.

"These are all very, very important questions, and I believe they will be centre stage this weekend in Washington."

The US is expected to use the summit to also push for a resolution to the long-running Doha round of world trade talks, which some believe could be the tonic to help the globe out of its current slump.

AAP