The US has welcomed Pakistan's President Asif Ali Zardari's visit to India on Sunday, calling it "very constructive".
Mr Zardari will visit, in a private capacity, the shrine of a famous Sufi Muslim saint in Rajasthan state.
He will meet Indian PM Manmohan Singh for lunch before visiting the shrine in Ajmer city.
This will be the first visit to India by a Pakistani head of state for seven years.
The visit comes as tensions ease between the nuclear-armed neighbours amid efforts to improve mutual trade over the last few months, correspondents say.
US State Department spokesman Mark Toner said Mr Zardari's visit to India was "very constructive and we are all for it".
"To us it's a win-win situation when Pakistan and India are engaging in dialogue, are talking to each other and are building better co-operation," Mr Toner was quoted as saying by the AFP news agency.
Days after Pakistan announced Mr Zardari's trip to India, the US offered a $10m (£6.2m) bounty for Hafiz Mohammad Saeed, the founder of Pakistan-based militant group Lashkar-e-Taiba [LeT].
Mr Saeed now heads the Jamaat-ud-Dawa (JuD) group, widely seen as a front for LeT - which is blamed for the 2008 Mumbai attacks in India. Both JuD and LeT are blacklisted by the US.
Mr Toner said the US was in "very close touch" with the Indian government on gathering evidence of Mr Saeed's alleged involvement in the Mumbai attack.
This would be Mr Zardari's first visit to India since he took over as president in 2008.
The last Pakistani president to visit India was Gen Pervez Musharraf, who came on an official visit in 2005.
Dialogue between India and Pakistan is being strongly encouraged by the United States in particular, as it is keen to promote regional stability ahead of the withdrawal of Nato-led forces in Afghanistan, correspondents say.