Indian Ambassador to the United States Ronen Sen on Monday condoled the death of US Congressman Tom Lantos, by saying India has lost a "true friend" in his death.

Offering his condolences to Lantos's family, Sen said in the death of Lantos, India has lost a strong supporter of bilateral relations.

"I am saddened at the death of Congressman Tom Lantos. We have lost a champion of democracy, a true friend of India and a strong supporter of closer Indo-US relations," Sen said in a statement.

"His leadership was invaluable in the passage of the enabling legislation in the US Congress for India-US civil nuclear energy cooperation," he added.