Washington: Leading Democratic senators are calling for the repeal of a Cold War-era law that has complicated US trade relations with Russia.

Without action to eliminate the 1974 Jackson-Vanik law, US companies will be shut out of trading opportunities after Russia gains entry to the World Trade Organisation this year.

At a hearing on Friday, the Chairman of the Senate Finance Committee, Sen Max Baucus warned that US companies could lose business to China and European countries.

"To allow American businesses, workers, farmers and ranchers to seize the opportunity that Russia joining the WTO presents, Congress much Act," Baucus said.

Baucus's committee would have to approve legislation repealing the law before it could be considered by the full Senate. The legislation also would need to be approved by the House of Representatives and signed by the president.

Jackson-Vanik denies normal trading relations with communist countries that restrict emigration or punish those trying to leave the country.

US presidents have granted Russia annual waivers to the law since 1994, so it has not affected the country's business interests since then.

Because Jackson-Vanik is against WTO rules, Russia would not be required to enforce WTO requirements for trade with the United States unless it is repealed.

Still, the move to repeal the law faces opposition by lawmakers from both parties concerned about Russia's human rights record.

Some want to tie repeal to new legislation slapping sanctions and travel bans on Russian officials engaged in human rights violations or corruption.

It was unclear whether lawmakers seeking an unconditional repeal of Jackson-Vanik have the votes to push it through.