British ground troops will not be drawn into combat operations against al Qaida-backed rebels in Mali, ministers have insisted.
The Foreign Office said the UK was providing only "limited logistical support" in support of the French military mission in the west African state, with no plans to deploy ground forces.
The first of two giant RAF C-17 transport aircraft left Paris on Monday night with supplies for the French force sent in by president Francois Hollande following an appeal for help by the Mali government. A second C-17 is expected to leave on Tuesday after encountering what was described as a "minor technical fault" in the French capital.
Foreign Office minister Mark Simmonds said a "small detachment of technical personnel" was already at the airport in the capital, Bamako, to "operate and if necessary defend" the aircraft. In a Commons statement he said David Cameron had made clear Britain was offering only limited back-up support when he spoke to Mr Hollande at the weekend.
"The Prime Minister has made categorically clear that the initial supporting deployment will be for a period of one week," he said. "He has also made clear that there will be no combat troops from the UK involved and we have no plans to provide more military assistance."
Earlier Mr Cameron said he agreed to help because France was "a strong ally and friend" of Britain, and because the military intervention was in UK interests.
"So we were first out of the blocks, as it were, to say to the French, 'We'll help you, we'll work with you and we'll share what intelligence we have with you and try to help you with what you are doing'," he said.
Mr Simmonds described how the situation in Mali was of "grave concern" to the UK and that it was essential to prevent the rebel-held north becoming a "springboard for extremism" in the region, saying: "With the international community, the UK has been concerned by the potential for terrorist groups to establish a safe haven in northern Mali which, if left unchecked, could pose a threat to Europe and the UK, as well as our interests in the region."
Meanwhile the European Union said it was bringing forward a planned military training mission to Mali, which will now be launched "in the second half of February or early March". Hundreds of French troops were deployed to the country on Saturday after the rebels overran the strategically important town of Konna on Thursday.
Despite the presence of the French, the government forces suffered a further setback on Monday with the loss of the garrison village of Diabaly in central Mali, taking the rebels within 250 miles of Bamako. Former foreign office minister Peter Hain expressed scepticism at predictions by the French that their troops would be out of the country "in a matter of weeks", saying: "That seems to me pretty unlikely. This could become an incredibly long, drawn-out and difficult morass."