The US military is thought to be the only force capable of launching such attacks in the region The Foreign Office says it is investigating reports that two white British al-Qaeda members have died in a suspected US drone raid in Pakistan.
The Muslim converts were reportedly killed in a missile attack near the town of Datta Khel five days ago.
The men, said to be aged 48 and 25, were apparently in a vehicle with two other fighters at the time.
The Foreign Office said the British High Commission in Pakistan was seeking further information.
According to the Guardian newspaper, the pair were using the pseudonyms Abu Bakr and Mansoor Ahmed.
The paper said if the deaths are confirmed, the men would be the first white British converts to have been killed in the area.
In September, a British terror suspect was killed in a drone attack in north-west Pakistan.
The BBC was told Abdul Jabbar was being groomed to head an al-Qaeda splinter group in the UK.
According to BBC Newsnight, Jabbar was tasked with preparing Mumbai-style commando attacks against targets in Britain, France and Germany.
The US military does not routinely confirm drone operations, but analysts say they are the only force capable of deploying such unmanned, remotely-piloted aircraft in the region.
Pakistan publicly objects to the strikes, but analysts believe such raids have the private backing of officials.
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