US Senate Republicans said last week they would try again to reform the asbestos litigation system with a reworked proposal introduced on Wednesday, but acknowledged they faced an uphill battle.

Last month reported that asbestos reform was set to be brought before Congress on April 19 and last week the bill was revealed to the lawmakers before the vote.

No date had as yet been scheduled for the more general problem of tort reform.

A spokesman for a key Senate Democrat said the proposed legislation appeared to be a partisan effort from the Republicans, lessening its chances of success in the closely divided Senate.

Senate Republican Leader Bill Frist announced the bill, a rewrite of a proposal Utah Republican Senator Orrin Hatch made last year to end asbestos lawsuits and establish a fund to pay claims of those sickened by exposure to the fibrous mineral.

Asbestos was widely used for fireproofing and insulation until the 1970s.

Scientists say inhaled fibres are linked to cancer and other diseases.

The seemingly endless litigation process in the US has been a huge problem for insurers who have had to put more and more money aside to cover possible future claims.

The insurance industry has been clamouring for reform, arguing that the lawyers involved are taking most of the money awarded and are a powerful lobbying force on the Hill.

Companies have paid out an estimated $70 billion on some 730,000 asbestos personal injury claims, making it the most expensive type of litigation in US history, according to the RAND Institute for Civil Justice. Last year alone, 100,000 claims were filed in US courts.

Sen. Frist said some improvements had been made on Hatch?s proposal from last year, such as increasing amounts that would be paid by the proposed fund to asbestos victims.

The bill envisions setting up a $114 billion asbestos trust fund, to be financed by asbestos defendant companies and insurers.

Sen. Frist, a Tennessee Republican, said he would seek a floor vote after the Senate returns from spring recess later this month.

He said he wanted it to be a bipartisan bill. But only one Democrat is a co-sponsor so far, and that senator, Zell Miller of Georgia, often votes with Republicans.

Sen. Hatch, speaking to the Senate after Sen.. Frist, denounced the ?voracious personal injury lawyers? he said had blocked progress on asbestos reform proposals to date by lobbying senators to oppose change.

?I fully expect that passing this legislation is going to be an uphill battle due to the strong grip of the powerful personal injury bar,? Sen. Hatch, chairman of the Senate Judiciary Committee, told the Senate.

David Carle, a spokesman for Vermont?s Sen. Patrick Leahy, the ranking Democrat on the Judiciary Committee, said Sen. Leahy had asked repeatedly to see the reworked bill, but had not seen it.

?It appears to be a partisan bill, and that will make it far more difficult to accomplish what needs to be done to address the asbestos problem,? Carle said.

Sen. Hatch?s bill was approved by the Senate Judiciary Committee last summer, but it stalled afterward and was never brought to the Senate floor. Sen. Frist has been trying to resurrect it ever since.

But he has not gained the support of labour unions, considered key to getting Democrats on board.