Unmanned aircraft are a key military resource that Britain must continue to fund after it withdraws from Afghanistan later this year, a committee of British lawmakers has said.

Britain's development of remotely piloted air systems, usually called drones, over the past decade helped to make military operations effective in Iraq and Afghanistan, the parliamentary Defence Committee said.

It is of vital importance that a clear distinction be drawn between the actions of UK Armed Forces operating remotely piloted air systems in Afghanistan and those of other States elsewhere UK Defence Committee

The intelligence, surveillance and reconnaissance support they gave troops on the ground had "undoubtedly" saved lives and prevented casualties, said the committee, which scrutinises government defence policy and expenditure.

"With the final withdrawal of forces from Afghanistan now rapidly approaching, Ministry of Defence thinking must turn to the future for the UK's existing remotely piloted air systems. We consider it to be a key capability which must continue to be supported," the committee said in a report published on Tuesday.

Unmanned air systems have so far been funded as urgent operational requirements and have not been budgeted for in long-term planned equipment spending, it said. Britain is due to hold its next strategic defence and security review (SDSR) in 2015, the year of a national election.

"We expect future development, in partnership with allies, to form an important strand of the SDSR 2015 equipment programme," said the committee, which includes lawmakers from both from the governing Conservatives and Liberal Democrats, as well as the opposition Labour party.

Britain and France agreed in 2012 to work together on unmanned aircraft. They announced plans for a 120 mln-pound ($197.9 mln) two-year study of the technology.

European drone

EU leaders also pledged in December to begin projects for developing a European drone between 2020 and 2025, although a British Defence Ministry source at the time made it clear Britain would not take part.

The committee said continuing a partnership with the United States Air Force after Afghanistan would give Britain access to future upgrades to its Reaper drones, built by privately owned US firm General Atomics. It would also offer chances for training that British airspace restrictions would make harder to carry out in the UK.

It also said other European NATO nations, including France and Italy, were also operating Reaper drones, so it might be helpful to form greater collaborations at a European level.

The committee noted the controversy around using drones in counter-terrorism operations. Last year saw the United States accused of breaking international law by killing civilians in drone strikes aimed at militants in Pakistan and Yemen.

"It is of vital importance that a clear distinction be drawn between the actions of UK Armed Forces operating remotely piloted air systems in Afghanistan and those of other States elsewhere," the committee said.

"On the basis of the evidence we have received we are satisfied that the UK remotely piloted air system operations comply fully with international law."