The centrepoint of his visit to New Delhi is talks over a nuclear cooperation deal. Bush will meet Prime Minister Manmohan Singh after a ceremonial reception at the presidential palace.

While the three-day visit is welcomed by many in India as a sign of growing recognition that Asia's third-largest economy is emerging as a regional power, it has angered Islamic and communist groups who oppose US policies such as the invasion of Iraq. On Wednesday, tens of thousands of anti-Bush demonstrators took to the streets, burning an effigy of the US leader and chanting slogans such as "Go back, Bush" and "Bush is a killer".

About 100,000 Muslim men gathered in the heart of the Indian capital shouting anti-Bush slogans, as hundreds of policemen in riot gear kept watch.

In the eastern city of Kolkata, a leftist stronghold, about 25,000 communist supporters converged on the city centre for a public meeting organised by the Committee Against Bush Visit.

"Under President Bush, the US continues to occupy Iraq and oppress its people. It threatens Syria and has targeted Iran on the issue of its nuclear programme," the committee said in a statement.

NUCLEAR PACT

The nuclear pact, under which India would get access to US technology in return for opening its civilian facilities to inspection and separating them from military plants, has run into opposition in Washington because India has not signed the nuclear Non-Proliferation Treaty.

There are also differences over the details.

However, both sides have tried to play down expectations even as they continue to discuss the number of reactors India will declare as civilian.

"It's a difficult issue," Bush told reporters in Afghanistan. "It's a difficult issue for the Indian government, it's a difficult issue for the American government.

"So we'll continue to dialogue and work. Hopefully, we can reach an agreement. If not, we'll continue to work on it until we do.

"Our relationship with India is broader than our discussions about energy. Ours is a strategic relationship."

India's extensive atomic weapons programme to counter neighbouring Pakistan and China's nuclear arms is a further concern for some members of the US Congress, who have cast doubt on the viability of any deal between Singh and Bush.

During his visit to Afghanistan, Bush met President Hamid Karzai and his US-backed government that took power after the Taliban regime was overthrown for refusing to hand over al Qaeda leaders after the Sept. 11 attacks.