The senator drafting a bill that aims to compensate asbestos victims from a trust fund said on Tuesday he hoped to have the measure completed by early February.

Sen. Arlen Specter, the Pennsylvania Republican who chairs the Judiciary Committee, conceded the size of the fund remained contentious and that his timetable was ambitious.

But in remarks to a committee hearing on the fund, Specter urged interested parties to work together on the details.

“This may well be the last, best chance, to deal with this issue in the foreseeable future,” he said.

Democratic and Republican lawmakers working on a similar bill last year agreed to $140 billion. Labor representatives say the funding should be at least $149 billion.

Specter said the previous agreement on $140 billion “makes that figure entitled to weight.”

Asbestos, a fire-retardant mineral, was once widely used for insulation and construction purposes. Scientists say inhaled fibers are linked to cancer and other diseases. Over 100,000 new asbestos claims were filed in 2003 and dozens of firms have gone bankrupt after being swamped by claims.

Sen. Patrick Leahy of Vermont, the ranking democrat on the committee, gave his support to the trust fund approach.

“We have to see our efforts through until we have a balanced and effective national trust fund that fairly compensates victims,” Leahy said.

President George W. Bush last week urged Congress to reign in asbestos lawsuits, saying asbestos claims had become “a national problem” clogging courts and bankrupting companies, while making it hard for the truly sick to get compensation.

Specter is proposing a fund to compensate victims while curbing their right to sue. The fund would be managed by the Department of Labor but privately financed by asbestos defendants, their insurers and some existing settlements.

Beyond the overall amount of money, Specter needs to bridge wide differences of opinion over other issues, such as whether claims can revert back to the court system if the fund has trouble starting up, or runs out of money.

National Association of Manufacturers President John Engler said in his prepared testimony that the maximum size of the fund must be $140 billion.

The bill should also “completely shut down the broken asbestos tort system,” Engler said, instead of allowing some leakage of claims back into the system.

Engler also complained about language that appears to allow asbestos claims to be recast as claims over injury from another mineral, silica.

“We believe that the bill must contain stronger provisions to lock the back door so trial lawyers don’t just convert tens of thousands of unimpaired asbestos claims into silica claims,” Engler said.