WASHINGTON (AFP) - US President Barack Obama congratulated Narendra Modi and said he was looking forward to working with him after he was sworn in as Indian prime minister on Monday.

"As the president and prime minister agreed in their call after the election, as the world's two largest democracies, India and the United States share a deep bond and commitment to promoting economic opportunity, freedom, and security for our people and around the world," a White House statement said.

"We look forward to working closely together with the new government to continue to strengthen and expand the US-India strategic partnership for years to come."

Mr Modi was controversially refused a visa to visit the United States in 2005 over allegations he turned a blind eye or worse to deadly anti-Muslim riots in the western state of Gujarat three years earlier.

The US State Department has said that Mr Modi will face no problems visiting the United States as prime minister because he will receive a special A-1 visa as a head of government.

Mr Modi, 63, was sworn in with the strongest mandate of any leader for 30 years, promising to forge a "strong and inclusive" country on a first day that signaled his bold intentions.