Finance ministers and central bankers from the Group of 20 rich and emerging countries, and the smaller Group of Seven developed nations, were scheduled to discuss on Thursday the impact of

high oil prices, huge government debts and Japan's disasters.

US Treasury Secretary Timothy Geithner, speaking at a conference on the global economy, said the recovery from the 2007-2009 financial crisis was intact and that investment and hiring was starting to pick up.

"Despite the risks in oil, the financial challenges still facing parts of Europe, despite what's happened in Japan ... what you see is gradual healing, gradual strengthening in confidence that the world economy is going to be growing at a reasonable rate," he insisted.

As officials gathered, Greek borrowing costs hit new highs.

Investors were spooked as Germany suggested a debt restructuring by Athens may be unavoidable.

French Finance Minister Christine Lagarde told reporters no talks were under way about restructuring Greece's debt. Athens is struggling to cut spending enough to meet commitments made

in return for a 110 billion-euro ($160 billion) bailout from the European Union and International Monetary Fund.

"There is a plan, there is delivery, there are (financial) installments. There is no discussion of debt restructuring as far as Greece is concerned. None whatsoever," she said.

The G7 countries — the United States, Britain, Canada, France, Germany, Italy and Japan — meet behind closed doors in the evening to assess the economic damage from Japan's earthquake and uprisings in the Arab world.

The IMF, which holds its twice-yearly meetings this weekend, warned officials not to grow complacent about the recovery's prospects simply because the worst of the financial crisis had passed.

"The apex of the crisis is behind us but it would be part of the complacency I am trying to avoid to believe we are in a post-crisis era," IMF chief Dominique Strauss-Kahn said.

The larger G20 club of advanced and developing economies holds a working dinner after the G7 meets to push forward on a plan for building a global economy less prone to the booms and busts that have marked the last two decades.

Neither group is expected to release a statement on Thursday, with the G20 waiting until it wraps up a day-long meeting on Friday.

The G20 is aiming to secure a deal on standards it can use to assess whether individual economies harbor imbalances, such as overly large trade deficits or surpluses, that could threaten the global economy.

China has expressed suspicion that the effort may be aimed at pressuring it to bring down its hefty trade surpluses.

New figures on Thursday showed China's foreign exchange reserves had soared to a record of more than $3 trillion by the end of March, which seemed certain to raise eyebrows among officials in Washington.

In the process of acquiring foreign exchange, China issues yuan in such volume that it keeps the currency's value at levels many countries consider unfairly low.

The G20 has become the premier forum for figuring out how to make sure there is no recurrence of the financial crisis that triggered the worst global recession since World War II.

G20 leaders agreed in 2009 to shrink imbalances between export-rich countries such as China and debt-burdened consumer economies like the United States. Many economists blame such

imbalances for sowing the seeds for the crisis.

But as the world economy recovers, the G20 has found it increasingly difficult to forge consensus on exactly how to lay the groundwork for more stable growth.

The G20 is expected to complete work on a set of "indicative guidelines" to spot potential trouble spots, although identifying specific countries running afoul of the rules would come later.

Lagarde suggested the biggest economies — those representing 5 percent or more of global output — might get special scrutiny because they are so big they could drag down the rest of the world economy if they stumbled.

The United States, China, Japan and Germany would fit that category but no others. "That is the threshold we consider as appropriate and relevant," Lagarde said.