Bipartisan bill in US Senate proposes tougher sanctions against Iran

US lawmakers in the Senate will be voting on a tough new round of sanctions against Iran on Thursday, after two top Democrat and Republican senators came out with a bipartisan bill that aims to isolate the Islamic republic.

Senate banking committee chairman Tim Johnson, a Democrat from South Dakota and Richard Shelby, the panel's top Republican, hammered out the 61-page bipartisan bill that other senators will vote on Thursday.

''A nuclear-armed Iran would represent a grave threat to regional peace and international security,'' said Johnson. ''Iran's continuing defiance of its international legal obligations and refusal to come clean on its nuclear programme underscore the need to further isolate it and its leaders.''

The move comes weeks after US President Barack Obama signed a new law on December 31, tightening banking sanctions against the Iranian regime, which has also been endorsed by Europe. The administration's tough new banking sanctions followed a bipartisan move in the Senate last year – which was voted 100-0 – targeting financial institutions doing business with Iran's central bank.

However, the two senators on the banking committee felt that existing sanctions and embargoes were not adequate to prevent Iran from building a nuclear bomb.

The new provisions proposed in the bipartisan bill would impose sanctions on companies involved in joint energy ventures anywhere in the world in which Iran has a stake. Penalties would also be imposed on companies involved in joint ventures with Iran in the mining, production or transportation of uranium, and on shippers or insurers who knowingly help Iran in building weapons of mass destruction.