A Briton and two Afghans have been kidnapped in Afghanistan, the Taliban has claimed.
The kidnapping is said to have happened on Monday in the southern province of Helmand. The Taliban gave no further details.
"All we can say is that we are looking into these reports," a Foreign Office spokesman said.
A Ministry of Defence spokesman said: "We are certainly not aware of any British soldier being kidnapped." And Prime Minister Tony Blair's official spokesman said: "We are still investigating on the ground and therefore I think we need more information before we can comment in any way."
A Taliban spokesman claimed the hard-line militia had detained the Briton - whom he did not name but said had claimed to be a journalist - and two Afghans as they travelled together by vehicle in the Nad Ali district of Helmand province.
"Taliban higher authorities" will decide what to do with them, Qari Yousef Ahmadi, who claims to speak for the Taliban, told the Associated Press. "We are investigating whether they are British spies."
Afghan officials had no immediate information on the reported kidnapping.
Meanwhile, Nato revealed that a coalition soldier had been killed in action in southern Afghanistan. No further details were immediately available about the incident, and the Ministry of Defence declined to comment.
The death came as a major new combined offensive was launched in the northern part of Helmand province.
Codenamed Operation Achilles, the push against the Taliban and drug traffickers will eventually involve 4,500 troops from Nato's International Security Assistance Force (Isaf) and 1,000 troops from the Afghan National Security Forces (ANSF).
