Halliburton Co., the oil-field services firm once headed by Vice President Cheney, is close to a $4 billion agreement that would settle about 300,000 asbestos claims and spare the company from bankruptcy, the company and lawyers involved in the case said yesterday.

Halliburton said in a statement that the settlement would involve up to $2.8 billion in cash and 60 million shares of stock, which would be placed in a trust to pay claims from people injured or sickened by contact with asbestos. The arrangement is similar to one pioneered by Johns-Manville Corp., the dominant player in the asbestos industry when injury claims swamped it in the early 1980s.

Asbestos suits have forced 20 companies into bankruptcy since January 2000, including Owens Corning and Federal-Mogul Corp., and may ultimately cost U.S. businesses more than $200 billion, according to some estimates.

The claims, against Halliburton subsidiary DII Industries LLC, have been pending in a bankruptcy court in Pittsburgh. A hearing in that court yesterday was postponed until tomorrow, apparently to allow the companies and the claimants to hammer out details.

The lawyers warned, however, that the deal may yet collapse.

"I am cautiously optimistic," said one lawyer involved in the case.

Halliburton inherited the asbestos claims in the Pittsburgh case when it acquired Dresser Industries in 1988, a deal that Cheney negotiated.

The high-stakes battle over them has been going on since the late 1990s, as more and more asbestos claimants appeared and lawyers sought to reach past the subsidiary to tap the assets of Halliburton. But the Republican election victory last month has introduced a new element into the case: the potential for federal tort-reform legislation that could sharply cut damage awards, and attorneys' fees along with them.

Lead plaintiffs' attorney Fred Baron of the Dallas firm Baron & Budd alleged last month that Halliburton was attempting to use the specter of tort reform as bargaining leverage to press for a settlement.

At the same time, another attorney in the case suggested, a settlement could be in the interest of Republicans who favor tort reform. "One of the nice things, if this deal works, it helps in Washington because it takes [the accusation that] we're bailing out Dick Cheney off the table," this attorney said.

The settlement would resolve not only pending claims but future ones as well, potentially as many as 800,000, attorneys said. That figure is based on a projection of future claims nationally and the assumption that Halliburton would probably be named in all or almost all of them.

Resolving those future claims, however, could bring some claimants to court to object to the deal. In a case like this, lawyers attempt to get as much as possible for their current clients and may succeed in winning a premium for them. But if others, whose claims are not being settled, conclude that it would mean less money left in the pot for them, they and their attorneys might attack the settlement.

Under the agreement, Halliburton would issue $1.4 billion in stock to fund a trust to pay future asbestos claims. The company would also borrow $2.75 billion to resolve pending lawsuits and pay previous but unpaid settlements and asbestos jury awards, lawyers said.

Attorneys' fees would take at least a third of the settlement, one lawyer estimated.

Asbestos is a fibrous silicate mineral that was widely used in industry until the late 1970s. Products such as fireproofing, insulation, spackling compounds and auto brake shoes contained it or were made of it. The tiny fibers, when inhaled, can cause severe lung damage and have been linked to a rare form of cancer, mesothelioma.

Tens of thousands of people who either worked with asbestos or came in contact with it have suffered lung damage, and many have died.

The Manville Trust has recorded 600,000 claims so far and the total could eventually reach 2.7 million. As funding mechanisms of this sort are exhausted and primary asbestos producers seek bankruptcy protection, litigation has expanded to include dozens of leading industrial companies.