President Barack Obama's drive to build relations with both India and Pakistan faces a delicate test Sunday as he meets with the leaders of the nuclear-armed rivals to discuss security issues.
Obama is expected to meet Prime Ministers Manmohan Singh of India and Yousuf Raza Gilani of Pakistan within hours, on the eve of a 47-nation summit on improving nuclear security.
But no meeting has been scheduled between Singh and Gilani. The two nations cautiously resumed talks in February which had been cut off after the deadly Mumbai assault in 2008.
Robert Blake, the assistant secretary of state for South Asia, said that the "pace, scope and character of relations" between India and Pakistan was up to the two countries.
But he added: "The United States hopes that India and Pakistan can improve relations between two friends of the United States."
Obama invited Singh in November for the first state dinner of his presidency, an honour meant to push forward a decade-old drive to transform the world's two largest democracies into partners.
The Obama administration has at the same time welcomed Pakistani actions against Islamic extremists and tried to curb widespread anti-Americanism in the country by seeking cooperation on issues beyond Afghanistan.
At a first-of-a-kind strategic dialogue with the United States last month, Pakistan presented one item on its wish-list: a US role in Kashmir, the divided Himalayan territory at the heart of two wars with India.
The United States has publicly ruled out mediation over Kashmir, which India considers a domestic issue. But some supporters of India have worried the Obama administration may put subtle pressure on New Delhi.