US Secretary of State Hillary Clinton landed in India on Sunday with hopes of reinvigorating a relationship seen as losing steam despite efforts to bring the world's two largest democracies closer.
Clinton was greeted by streets lined with waving well-wishers as she started her visit in Kolkata, where she will tour monuments and meet ordinary citizens in her latest bid to use her star appeal as a diplomatic tool.
She heads on Monday to New Delhi for talks with Prime Minister Manmohan Singh with whom she is expected to raise US calls for India to stop buying oil from Iran, one of the most open disagreements in years between the countries.
Clinton said she saw ample progress in relations with India, pointing to rising trade and cooperation in areas from education to clean energy.
"I think it's like any relationship -- there is progress in some areas that we are very heartened by, and there is more work to be done," Clinton told reporters before her arrival.
"But that's the commitment that we make when we say to another country, we want to be your partner," she said.
After more than a decade of warming relations, India has bristled at a US law that would impose sanctions on banks from countries that buy oil from Iran due to concerns over Tehran's contested nuclear programme.
A senior US official travelling with Clinton acknowledged that India had quietly been cutting back on Iranian oil and that New Delhi -- fiercely protective of its sovereignty -- could not be seen as buckling under US pressure.
"Our assessment is that India is making good progress but we really need to receive assurances that they're going to continue to make good progress," the official said on condition of anonymity.
The official said that Carlos Pascual, the US pointman on the issue, would visit New Delhi later this month to determine the next step. Only EU nations and Japan have so far been given exemptions to the sanctions which go into effect on June 28.
India is highly dependent on foreign energy and has historically enjoyed friendly relations with Tehran.
But the US official said that Indian businesses had made "a major strategic bet" on continuing good relations with the United States and did not want to jeopardise them over Iran.
Clinton will meet Monday morning in Kolkata with West Bengal's Chief Minister Mamata Banerjee, who took power last year by sweeping out nearly 35 years of communist rule in the eastern state.
Clinton will seek to show solidarity with a fellow female leader but also press Banerjee to back the opening up of India's fast-growing retail sector to major foreign companies such as Walmart, the US official said.
Banerjee, a fractious ally of Singh's government, was instrumental in scuttling planned retail reforms. Critics charge that liberalising the sector would devastate India's ubiquitous small stores, but foreign retailers contend that they can improve efficiency and consumer choice.
US businesses, once at the vanguard of building ties with India, have voiced disappointment over the deadlock on retail reform along with parliament's refusal to give US nuclear firms greater protection from liabilities.
Nuclear energy had been a symbolic milestone in the relationship, with former president George W. Bush championing a deal that ended India's decades of isolation over its nuclear Non-Proliferation Treaty.
President Barack Obama has backed another of India's longtime ambitions by supporting its bid for a permanent seat on the UN Security Council. But few expect UN reform anytime soon and some Indians have accused the Obama administration of a lack of attention.
T.P. Sreenivasan, a former Indian ambassador to the United Nations, said that the initial expectations for the US-India relationship had not been met but that Clinton had the advantage of being considered a friend of New Delhi.
The visit "comes at a useful time as there is a certain amount of strain in relations that needs to be rectified," he said.
"The relationship has lost momentum partly because... both are preoccupied with their own internal problems," he said.