A British coroner will oversee a post-mortem examination of the body of kidnapped UK aid worker Linda Norgrove, who was killed in Afghanistan.
The move was announced by Prime Minister David Cameron's office.
Ms Norgrove was killed last week during a rescue attempt by US special forces.
The mission was sanctioned by Mr Cameron, who has condemned the "cowardly and ruthless" militants who took her hostage.
Speaking at Prime Minister's Question Time, Mr Cameron said he had stressed to US President Barack Obama that it was "extremely important" there should be a joint US-UK investigation into the death of Ms Norgrove, who was killed last week.
A joint US/UK military inquiry was launched after evidence suggested she may have been killed by a US fragmentation grenade and not, as first thought, by her captors.
That inquiry is being led by Brigadier Rob Nitsch, the Head of Joint Force Support, UK Forces Afghanistan and senior US investigating officer Major General Joseph Votel.
Mr Cameron said he would discuss Ms Norgrove's death with the US commander in Afghanistan, General David Petraeus, on Thursday.
Labour leader Ed Miliband has given his support to the decision to authorise the rescue mission.
National Security Adviser Peter Ricketts will meet the Head of US Central Command Afghanistan, General James Mattis, later on Wednesday to discuss the case.