The three soldiers had been on board a Canadian army Griffon helicopter
A British soldier has been killed in a helicopter accident in Afghanistan, the Ministry of Defence has said.
The soldier, from 22 Engineer Regiment, Royal Engineers, died alongside two Canadian troops when their aircraft crashed in Zabul province on Monday.
A safety investigation had already "determined that the crash did not occur as a result of enemy fire," a Nato spokesman said.
The British soldier's next of kin had been informed, the MoD said.
The soldier's name has yet to be released. The Canadians who died have been named by Canadian media as Master Cpl Pat Audet and Cpl Martin Joannette.
The three men had been on board the Canadian army Griffon helicopter when it crashed shortly after taking off from a US forward operating base in Zabul province, about 80km (50 miles) north-east of the city of Kandahar at 1350 local time (0920 GMT).
Three other Canadians, including the two pilots, were hurt, one seriously.
Griffons are used primarily as transport and escort helicopters. They have been deployed in Afghanistan since the beginning of the year.
A British military spokesman, Lt Col Nick Richardson, said: "Today has been a sad day in the history of Task Force Helmand and this death has deeply moved us.
"The loss of a soldier, friend and colleague is tragic and our thoughts are with his family and friends at this sad time," he added.
The soldier's death takes the number of UK service personnel killed in Afghanistan since October 2001 to 175. Six have died in less than a week.
The five others were killed while taking part in Operation Panchai Palang, or Panther's Claw, a joint mission by thousands of US, Nato and Afghan forces to improve security ahead of the Afghan presidential election next month by targeting several Taliban-controlled districts in southern Helmand province.
Seven US soldiers were killed in attacks across Afghanistan on Monday, four of them in the relatively peaceful north, in the deadliest day for US troops in a year.