The attack targeted a house in Mosakki village, about 25 kilometres (16 miles) east of Miranshah, the main town in North Waziristan, and was the third suspected US missile attack in the tribal district in less than a week.
"There may have been an important figure hiding in the house," a Pakistani security official in Miranshah told AFP on condition of anonymity because he was not authorised to speak about the sensitive strikes.
"A total of five militants have been killed, two are local and three are foreigners. One among the foreigners is an Arab," the security official said, adding that the identity of the other two was not yet known.
Suspected US drones have increasingly targeted North Waziristan, a bastion of Al-Qaeda fighters and the Haqqani network that attacks US and NATO troops fighting against the Taliban in neighbouring Afghanistan.
Washington is putting increased pressure on Pakistan to tackle militants who use its soil to launch attacks in Afghanistan and American officials have said that the highly secretive drone programme has eliminated some top fighters.
"One US drone fired two missiles on a house.... The target was this house and a car parked outside was also destroyed," a senior Pakistani security official earlier told AFP on condition of anonymity.
Local administrative and intelligence officials confirmed the attack and the death toll.
North Waziristan borders the Afghan province of Khost, where a suicide bomber killed seven CIA agents and an eighth American on a US base last week in the deadliest attack on the US spy agency since 1983.
Washington has put Pakistan at the heart of a new strategy for winning the eight-year war against the Taliban in Afghanistan, saying success depends on dismantling militant sanctuaries along the porous border.
Around eight US missile strikes in North Waziristan have killed 49 people in the past month, although the identities of those killed are hard to verify as the deaths are deep in Taliban-controlled territory.
The attacks on Pakistani territory fuel anti-American sentiment in the nuclear-armed Muslim nation and the government in Islamabad publicly condemns the strikes. Analysts say, however, that the strikes have Islamabad's tacit approval.
More than 70 US drone missile strikes have killed at least 665 people in Pakistan since August 2008. The United States does not confirm drone attacks, but its military is the only force that deploys drones in the region.
North Waziristan neighbours South
Waziristan, where Pakistan has been focusing its most ambitious military
offensive yet against homegrown Taliban militants. It sent about 30,000
troops into the region on October 17.