The regulatory plan is being put together ahead of the meeting of the Group of 20 industrialized and developing nations in London. The meeting, which begins April 2, is expected to be dominated by the global financial crisis and discussions about better oversight of large financial companies, whose problems could threaten to undermine international markets.

An important part of the plan still under debate is how to regulate the shadow banking system that Wall Street firms use to package and trade mortgage-backed securities, the so-called toxic assets held by many banks and blamed for the credit crisis.

Officials said the plan would also call for increasing the levels of capital that financial institutions need to hold to absorb possible losses. In a sign of the economic system’s fragility, officials said the administration would emphasize that those heightened standards should not be imposed now because they could discourage more lending. Rather, they would be put in place after the economy began to rebound.

“The argument some are making is that they don’t want to be stepping on the gas pedal and the brake at the same time,” said Morris Goldstein, a senior fellow at the Peterson Institute for International Economics and a former top official at the International Monetary Fund.

Administration officials are also debating how tightly to supervise hedge funds.

A broad consensus has emerged among regulators and administration officials that hedge funds must be registered and more closely monitored, probably by the Securities and Exchange Commission. But officials have not decided how much the funds will have to disclose about their investments and trading practices. The officials spoke on condition of anonymity because the regulatory plan was still being formulated and they did not want to upstage Mr. Obama or Treasury Secretary Timothy F. Geithner, who will describe the plan when he appears before Congress on Thursday.

A central aspect of the plan, which has already been announced by the administration, would give the government greater authority to take over and resolve problems at large troubled companies not now regulated by Washington, like insurance companies and hedge funds.

That proposal would, for instance, make it easier for the government to cancel bonus contracts like those given to executives at the American International Group, which have stoked a political furor. Under the proposal, the Treasury secretary would have the authority to seize and wind down a struggling institution after consulting with the president and upon the recommendation of two-thirds of the Federal Reserve board.