The Bickleigh barracks north of Plymouth is under review

The Ministry of Defence says Chivenor and Bickleigh are under review as part of plans for the "rationalisation" of the armed forces.

A letter to the county council says much detailed work needs to be done and all parties will be consulted.

But it stresses that no decisions have yet been made.

Chivenor near Barnstaple is home for about 600 Marines and their families, an RAF search and rescue unit, 150 engineers and an RAF cadet and volunteer glider school.

The base was due to close in 1992 when the RAF moved to Wales, but following a campaign, the MoD moved Royal Marines into Chivenor.

The council estimates it brings about �35m a year into the local economy.

Also under threat is the 550-strong 42 Commando based in Bickleigh, north of Plymouth, 3 Commando Brigade based at Stonehouse, Plymouth - where about 2,000 Marines are based - and 40 Commando Royal Marines based in Taunton, where 550 soldiers are stationed.

A letter from the MoD to Devon County Council Chief Executive Philip Jenkinson, says: "The Ministry of Defence has conducted a rigorous examination of force structure, specific requirements and supporting infrastructure and organisations.

"The aim of this work has been to ensure that we target increased defence expenditure at what armed forces require in the 21st century."

The executive committee of the council are due to discuss the issue next week.