Nawaz Sharif, Pakistan's prime minister, is due to meet the US president a day after calling for an end to drone strikes in his country and the release of an independent report stating such attacks could constitute war crimes.
The White House meeting on Wednesday, Sharif's first since he was elected in May elections, is expected to focus on the security of Afghanistan after the US pull-out next year, aid for Pakistan and the US drone programme.
Sharif on Tuesday called for warmer ties with the United States and offered Pakistan's assistance in Afghanistan as US forces prepare to withdraw .
But the prime minister said that the unmanned strikes violate international law and the "territorial integrity" of his country, and hurt bilateral relations.
"I would therefore stress the need for an end to drone attacks," Sharif said at the US Institute of Peace.
The comments followed the publication of a report by Amnesty International documenting drone strikes in Pakistan. Amnesty said many civilians had been killed, and that such attacks could constitute war crimes.
"We are reviewing these reports carefully," White House spokesman Jay Carney said.
"To the extent these reports claim that the US has acted contrary to international law, we would strongly disagree.
"The administration has repeatedly emphasised the extraordinary care that we take to make sure counter-terrorism actions are in accordance with all applicable law."
Carney added that Obama hoped to use the Wednesday meeting with Sharif to promote "a stable, secure and prosperous Pakistan that is contributing to regional and international security and prosperity".
Carney also said that by deciding to use drone aircraft, rather than sending in troops or using other weapons, Washington was "choosing the course of action least likely to result in the loss of innocent life".