Vienna/New Delhi, Oct 27 (IANS): Ahead of US President Barack Obama's visit, India Wednesday signed a global pact on nuclear liability in Vienna, a key step that will assuage concerns of US companies and enable them to resume nuclear trade with New Delhi.

Dinkar Khullar, India's ambassador to Austria and Permanent Representative to the International Atomic Energy Agency (IAEA), signed the Convention on Supplementary Compensation for Nuclear Damage (CSC) at the headquarters of the IAEA in Vienna.

With less than two weeks to go for Obama's Nov 6-9 visit to India, the Indian government decided to fast-track the signing of the CSC, which was sought by US nuclear companies, who were apprehensive of clauses dealing with suppliers' liability in the civil liability legislation enacted by parliament in August.

The nuclear liability legislation gives the operator the right to seek damages from atomic suppliers if there is an accident.

The signing of the CSC is considered part of New Delhi's commitments under the landmark civil nuclear pact it signed with Washington two years ago and is aimed at bringing the Indian domestic legislation in line with international norms.

Prime Minister Manmohan Singh is understood to have given his nod to signing of the CSC early this week amid signals from the US that the issue may cast a shadow over Obama's forthcoming visit. The signing of the CSC is also expected to clear the decks for the removal of restrictions barring high-tech exports to India, a widely expected highlight of Obama's November visit.

The US was quick to welcome India's signing of the CSC, a, long-standing demand of American nuclear companies.

"The US notes India's signing of the CSC. It will bring benefits to both countries, to suppliers and to the Indian people," US ambassador to India Timothy J. Roemer told reporters in New Delhi.

"It will help provide clean and affordable electricity to Indian people," the US envoy said hours after India signed the CSC.

The convention will give India access to a global fund for compensation in case of a nuclear accident with trans-national implications. Adopted on September 12, 1997, the convention has been signed by 14 countries, including India, but only four countries-- the US, Argentina, Morocco and Romania - have ratified the convention so far.

The CSC, after it enters into force, would establish a uniform global legal regime for compensation to victims in the event of a nuclear accident.

The convention also sets parameters on a nuclear operator´s financial liability, time limits governing possible legal action, requires that nuclear operators maintain insurance or other financial security measures and provides for a single competent court to hear claims.

At least five countries with 400,000 units of minimum combined installed nuclear power capacity have to ratify the convention before it comes into force.