A congressional committee is nearing agreement on a bill creating a stricter regulator for Fannie Mae and Freddie Mac in the wake of more than $13 billion in accounting mistakes at the two biggest American mortgage finance companies, the senior Democrat on the panel said yesterday.

“We’re close to the kind of bill we could have passed a while ago,” Rep. Barney Frank of Massachusetts, the senior Democrat on the House Financial Services Committee, said yesterday. “We’re working together well on it,” he said after a hearing in Washington, referring to meetings with Republicans in which he said he identified no major obstacles.

Committee Chairman Michael Oxley, a Republican from Ohio, said Tuesday that as early as May 18, the panel will pass legislation creating a regulator with power to alter capital standards, reject new lines of business, reduce the size of the companies, and sell off assets in the event of default at the two government-chartered enterprises.

The committee, differing with Treasury Secretary Snow and Federal Reserve Chairman Alan Greenspan, doesn’t believe it is necessary to reduce the companies’ combined $1.5 trillion mortgage portfolios, Mr. Frank said. Messrs. Snow and Greenspan called on Congress last month to cut the holdings in order to avert financial market instability.

“There is not a majority sentiment here for reducing portfolio limits for any reason” other than ensuring the “safety and soundness” of Fannie Mae and Freddie Mac, Mr. Frank said.

Fannie Mae interim Chief Executive Daniel Mudd and Freddie Mac Chief Executive Richard Syron told Congress on April 22 that a regulator should trim a loan portfolio only to prevent insolvency at one of the companies, known as government-sponsored enterprises, or GSEs.

The regulator would have power to “limit the portfolio, not as mandated in the law, but as the current situation demands,” Mr. Oxley said, expressing a view similar to that of Messrs. Frank, Mudd, and Syron. It should have authority to “reduce or even to increase a GSE’s assets or liabilities.”

Bipartisan support is growing on the committee for an amendment that would require Fannie Mae and Freddie Mac to set aside 5% of their profits to fund affordable housing projects and mortgages for low-income homebuyers, Mr. Frank said.

“There is new consensus now, which is actually a unifying one, which is the affordable housing program,” Mr. Frank said.

“What we’re saying now is, ‘Let’s require them to provide significantly more public benefit.’ “

The profit set-aside would total about $900 million, said Senator Reed of Rhode Island, a Democrat and sponsor of a similar proposal on the Senate Banking Committee.

Senator Sarbanes of Maryland, the senior Democrat on the committee, is helping to refine the proposal, Mr. Reed said. A bipartisan consensus behind the legislation is gelling on the committee, Joe Cwiklinski, an aide on the panel, said May 2.