Washington, Dec 16 (IANS) US concerns about India's nuclear liability law have been addressed by New Delhi signing an international treaty and assuring a level playing field for US companies, says a senior official.

"I think they have been," Assistant Secretary, Bureau of South and Central Asian Affair Robert Blake said in response to question during a conference call with journalists in South Asia Wednesday.

"I think as you saw in the Joint Statement, India announced that it has signed the Convention on Supplementary Compensation and they indicated they intended to ratify the CSC within the coming year and to ensure a level playing field for US companies," he said.

US companies that had been eyeing India's estimated $150 billion nuclear power pie had baulked after the passage of the liability law holding suppliers also liable for 80 years, putting the landmark India-US civil nuclear deal in jeopardy.

"So this will continue to be a very high priority for the United States not only because this represents a huge commercial opportunity for our companies in India," he said.

"But also because it will help our friends in India to meet their fast-growing energy needs and to diversify to new sources such as the civil nuclear, and increasingly also renewable energy where we're also working together," Blake said.

"We are moving ahead on the civil nuclear side where we were very pleased with the outcome of the President's visit, he said.

The government to government parts of the civil nuclear agenda had been completed and now US companies have begun negotiations to help provide reactors that can meet India's civil nuclear needs.

In response to another question, the US official said their biggest priorities are to move forward in all of the areas that President Barack Obama and Prime Minister Manmohan Singh discussed during Obama's landmark visit there in November.

"We have important priorities in the economic sphere where we want to expand our trade and investment between our two countries," he said. "That's already moving ahead very rapidly, but we think there's much more that can be done in that area."

The US also wanted to expand its global partnership into new areas such as working together on trilateral cooperation in Afghanistan, in Africa, on non-proliferation, on climate change, and in the UN Security Council where India will pick up its two year rotation beginning January 1st of next year, Blake said.