The missiles hit a compound in Shokhel village, more than 100 kilometres southwest of Miranshah, the main town of North Waziristan tribal district that is known as a stronghold of Taliban and al Qaeda-linked militants.
“The US drone fired two missiles targeting a militant compound and killing at least seven militants,” a senior local security official told AFP.
Another official confirmed the strike and casualties but said the identities of those killed were not yet known.
The strike came just two days after Sharif was sworn in for a historic third time and asked the United States to end its campaign of drone attacks against militants.
“We respect the sovereignty of others and they should also respect our sovereignty and independence. This campaign should come to an end,” he said after lawmakers endorsed him as premier on Wednesday.
He had also publicly criticised the drone strike that killed Taliban deputy Waliur Rehman last week, echoing long-held Pakistani complaints that the US campaign violates national sovereignty.
Waliur Rehman, the number two in the Tehreek-e-Taliban Pakistan (TTP) faction, died along with at least five others when a drone fired two missiles on a house in North Waziristan on May 29.
Waliur Rehman, who had a $5 million US government bounty on his head, was killed after US President Barack Obama outlined new more restrictive guidelines on drone use.
Washington had accused Waliur Rehman of organising attacks against US and NATO forces in Afghanistan and also wanted him in connection with a suicide attack on an American base in Afghanistan in 2009 that killed seven CIA agents.
Drone missile strikes are very unpopular in Pakistan, but Washington views them as a vital tool in the fight against Taliban and al Qaeda militants holed up in the lawless Tribal Areas along the border with Afghanistan.
Ties with Washington will be a key part of Nawaz Sharif’s tenure, particularly as NATO withdraws the bulk of its forces from Afghanistan by the end of next year after more than 12 years of war.
The families of Pakistani victims of US drone strikes on Thursday wrote to Nawaz Sharif urging him to stop the campaign – by shooting the unmanned aircraft down if necessary.
The Peshawar High Court on May 9 declared the CIA drone strikes targeting suspected militants to be a “war crime” and ordered Islamabad to take steps to halt them.
Victims’ families and their lawyer Mirza Shahzad Akbar have written to Sharif urging him to heed the court’s ruling, which calls on the government to take the matter up at the UN Security Council. Akbar said that if Pakistan failed to persuade the US to stop the strikes through the United Nations, “the court has very clearly ordered to shoot down the drones”.