WASHINGTON — The federal overseer of Fannie Mae and Freddie Mac on Tuesday announced policies that would maintain the mortgage giants’ role in parts of the housing market, spur more home lending and aid distressed homeowners.

The announcement is a significant shift in strategy for the mortgage financiers, driven by the new director of the Federal Housing Finance Agency, Melvin Watt.

“Our overriding objective is to ensure that there is broad liquidity in the housing finance market and to do so in a way that is safe and sound,” Watt said in remarks at the Brookings Institution in Washington.

Watt announced a number of changes for Fannie and Freddie, changes that would perpetuate the two government-sponsored enterprises’ presence in mortgage finance, rather than shrinking it.

Save 75% on a Digital Subscription Today

Fannie and Freddie — which back about two-thirds of new mortgages — will keep current limits on the size of loans they guarantee, rather than reducing those limits, as previously proposed.

“This decision is motivated by concerns about how such a reduction could adversely impact the health of the current housing finance market,” Watt said.

The new director also loosened rules that obligated banks to “buy back” distressed loans. Watt said the mortgage financiers will now allow two delinquent payments in the first 36 months after their acquisition of a loan, and that they would eliminate “automatic repurchases when a loan’s primary mortgage insurance is rescinded.”

Those changes might stimulate mortgage lending. Many banks have tightened credit standards, in part because of the requirement that they take losses if borrowers default.

In addition, Watt said he was looking into “an independent dispute resolution program when lenders believe a repurchase is unwarranted” and clarifying Fannie and Freddie’s underwriting rules. Watt said the housing institutions would do more to communicate with the 750,000 homeowners who might benefit from the Home Affordable Refinance Program, which helps homeowners modify their mortgage loans.

He said he would not change the eligibility requirements for that program, though, because the number of additional borrowers who might be helped is “relatively small.”

Watt’s remarks come as Fannie and Freddie have returned to profitability, and as legislators in Washington have started to consider how to remove them from government conservatorship.

The federal government rescued Fannie and Freddie from collapse in 2008, with a bailout that cost about $190 billion. Since then, they have stabilized their loan portfolios and paid about $200 billion in dividends to the federal government.

Both Democrats and Republicans have argued that the companies should be returned to the private market or wound down.

But the fragile state of the housing recovery and lingering concerns about lending regulations — along with the fact that Congress has failed to act even on issues with broad bipartisan agreement — has forestalled any legislation.

On Thursday, the Senate Banking Committee is due to vote on a bill that would wind the agencies down. But Congress is not expected to pass any reform measures in the foreseeable future.

Watt was confirmed as the head of the Federal Housing Finance Agency at the end of last year. His predecessor, Edward DeMarco, a civil servant who became the agency’s acting director, frequently clashed with Democrats, refusing to put in place a White House proposal to reduce the principal on so-called underwater mortgages.