The Armed Forces have only 40 paramedics who would be qualified to work in the NHS, the Government has disclosed.
Defence minister Dr Andrew Murrison said that of the 107 paramedics serving in the military, 40 have the qualification requirements set out by the Health and Care Professions Council.
The details, set out in a written answer to Liberal Democrat health spokeswoman Daisy Cooper, were disclosed as ministers prepare to deploy troops to cover for striking ambulance staff.
Ms Cooper said ministers must now get round the negotiating table to ensure the strikes are called off.
"The Government has got to sort this out now before people's lives are put at risk. Their patchwork plan to keep ambulance services running has filled the public with anxiety about the days to come," she said.
"Emergency health services have already been starved of funding by this Government leading to dangerously high waiting times, and will now be plunged into even more chaos if these strikes go ahead."
Ambulance crews in England are due to walk out for two days on 21 and 28 December in support of their pay claim.
Earlier this week, the Ministry of Defence (MOD) confirmed 750 military personnel would be deployed to cover ambulance strikes – with 650 from all three services are expected to drive ambulances, with the remaining 150 used in a logistical capacity.
It is understood that troops are unlikely to be used to drive ambulances to respond to urgent calls although they could be used for non-urgent cases to free up paramedics.
The Defence Secretary also said the strikes will "ruin the lives" of members of the Armed Forces.
Earlier, in the House of Commons, Labour shadow defence secretary John Healey said: "At today's Cobra meeting, will the Defence Secretary tell other ministers in other departments they are too often using our Armed Forces to bail out their own departments' failures, especially when he's making further deep cuts to the Army?
"Will he tell the House now, in addition to those deployed on overseas operations which he's mentioned, how many of our forces will be deployed or on stand-by over Christmas in response to requests for military assistance he's already agreed to?"
In response, Ben Wallace said: "I will do the right honourable gentleman a deal. I"ll raise that at Cobra if he tells his union paymasters to not go on strike over Christmas and not ruin the lives of our soldiers and sailors."