The RAF Sentinel will continue to provide information to British and coalition forces fighting Islamic State (IS) militants, Michael Fallon said.
Mr Fallon said the fight against IS militants remained the UK's "top operational priority". The announcement was made a year after MPs voted for military action in Iraq.The UK has been carrying out out surveillance and air-to-air refuelling operations in Syria although the government was defeated in a vote on military action in the country in 2013