The U.S. envoy to India has broken a long silence regarding the stalemate in the proposed nuclear cooperation agreement between New Delhi and Washington. As Steve Herman reports from the Indian capital, the American ambassador's comment is being viewed as a blunt warning to New Delhi to move ahead with the pact.

In remarks broadcast by an Indian cable television news channel, U.S. Ambassador David Mulford warned time is running out for India to clear the remaining hurdles if it wants to enact a controversial nuclear cooperation deal with the United States.

The deal is seen as crucial for helping India's growing economy overcome energy shortages in the years ahead.

In an interview with the CNN-IBN channel, Ambassador Mulford said elections in the U.S. will put a new administration in the White House and change the face of congress from next January. He says that means the window of opportunity for India to finalize the nuclear deal is closing.

"If this is not processed in the present Congress, it is unlikely that this deal will be offered again to India," said Ambassador Mulford. "It certainly would not be revived and offered by any administration, Democratic or Republican, before the year 2010, which is after the life of this particular administration in India."

Under the deal, Washington and New Delhi would have a new strategic relation that would give India access to nuclear fuel and equipment from the United States. India was frozen out of such a relationship for nearly 30 years because it had conducted nuclear weapons tests and did not sign international non-proliferation agreements.

Opponents of the deal worry it could help bolster India's nuclear-weapons stockpile and trigger a regional arms race. Political observers say such opponents might be more influential in the next Congress and the next presidential administration might not be as enthusiastic to take on lawmakers with such concerns.

The deal has also faced strong opposition from India's left, which objects to closer cooperation with the United States. Opponents in India also say the agreement would infringe on Indian sovereignty, because it might restrict India from conducting further nuclear tests.

Ambassador Mulford rejects arguments that the deal is designed to make India a subordinate ally of the United States.

"That is completely untrue," he said. "The reasons why this deal was initiated by the President of the United States were based on the statement that he made shortly before that initiative was taken - that the United States wanted to assist India in achieving its global vision of emerging as a major economic power in the world."

The ambassador says he would like to meet with the leader of India's communist party to ease the concerns of the left. The leader of the Marxist wing of the Indian Communist Party, Prakash Karat, has threatened to topple the government led by Prime Minister Manmohan Singh if the deal is concluded.

Mr. Singh's coalition government has endorsed the agreement. But in recent months it has moved slowly in getting the needed clearances from the International Atomic Energy Agency and the 45-nation Nuclear Suppliers Group required before the U.S. Congress can give final approval.

Indian officials say four rounds of talks with the IAEA have made progress, and India will not be pressured by any time frames or deadlines set by either domestic opponents or other governments.