G20 urges US to act quickly to avoid default

'Better than nothing'

Most of the attention, however, was on the risk of a US default, which has clouded the global economic outlook.

Siluanov said US Treasury Secretary Jack Lew left the gathering early to participate in debt talks.

"We trust that the administration and the Congress will arrive at a mutually acceptable solution," he said.

Lew has said the United States would be unable to meet all its obligations if the debt limit is not lifted by Oct 17.

Major US stock indexes rose on Friday on the heels of their biggest gain in nine months a day earlier as the Republican offer stirred hopes for a quick deal.

But there were also worrying hints of the chaos that could ensue if Washington were to miss a debt payment.

Banks and money market funds are shunning some Treasuries normally used as collateral for short-term loans, a sign that a deadlock over the debt ceiling could disrupt a key source of day-to-day funding in the financial system.

Hong Kong's securities exchanges plan to slap a bigger discount on Treasuries used as collateral.

"Politicians don't quite seem to have grasped how important the Treasury market is to the global financial system," HSBC chief economist Stephen King said.

While the Republican plan offered the hope of short-term relief, it could also bring the country back to the brink of default before year end.

"Whatever reduces uncertainty is positive but I think that really to reduce uncertainty in a substantial way we would need a long-term solution," said Ewald Nowotny, a member of the European Central Bank's Governing Council.

"Still, it seems to be better than nothing."