The Ministry of Defence confirmed on Friday it had suspended mid-air refuelling of its Nimrod spy planes after a fuel leak forced an emergency landing in Afghanistan earlier this week.
No-one was injured in the incident and the Nimrod fleet remains flying, a ministry spokeswoman said.
"During air-to-air refuelling on an operational mission, the crew observed a quantity of fuel spraying into the aircraft's bomb bay," she said.
"Following initial investigation, and isolation of the air-to-air refuelling system, the aircraft was flown back to its original operating base for further engineering investigation.
"As a precautionary measure air-to-air refuelling has been suspended for all Nimrod aircraft, until the results of a full investigation have been considered," she said.
A fuel leak is believed to have caused the loss of a RAF Nimrod plane in Afghanistan in September last year with the loss of all 14 crew.
A military inquiry into the incident is nearing conclusion, the spokeswoman said.
Two previous Nimrod crashes have been blamed on onboard fires and the pilot of the plane that crashed in Afghanistan had also reported a fire on board.
In February the Nimrod fleet was temporarily suspended for checks after a dent was found in the fuel pipe on one of the aircraft. ( Reuters )