Vince Cable said the £13bn project was too costly
A pan-forces training academy which would create thousands of jobs in south Wales should be scrapped, the Liberal Democrat Treasury spokesman has said.
Dr Vince Cable MP said the £13bn to set up the St Athan project was was too costly in the current economic climate.
The Ministry of Defence (MoD) announced two years ago that it was to train servicemen and women at the academy.
The largest facility of its kind in the UK, it will give specialist technical training to the three armed services.
The Ministry of Defence has estimated the academy in the Vale of Glamorgan would create 2,500 jobs on site, with a further 750 to 1,500 additional jobs in the wider economy and up to 1,500 jobs in the construction phase.
Dr Cable has today published an economic "recovery plan" which contains proposals for cutting government spending.
The Welsh Lib Dems say Mr Cable's comments were not party policy but indicated the levels of cuts needed in the current economic climate.
And a disclaimer on the Lib Dems website says: "Please note: this is not official Liberal Democrat policy and examples are illustrative and represent only a first, rough attempt."
A spokesman said that if the £13bn were not saved by scrapping the St Athan project it would have to be saved elsewhere, which would also have an impact on Wales.
'Jewel in the crown'
Welsh Secretary Peter Hain accused the Liberal Democrats of "competing with the Tories to make irresponsible cuts that will hurt the people of Wales".
"This is a jewel in the crown project," he said.
"It will make British forces the best trained in the world," Mr Hain added.
Responding, a Conservative spokesman said: "This project has always had cross-party support and we will continue to maintain that the military should be properly trained."
Accusing Dr Cable of making a "reckless proposal", local Labour MP John Smith insisted the scheme was "exactly the type of wise spending the British economy needs to help us come out stronger from the current economic storms".
Over the weekend, attempts by Plaid Cymru activists to commit the party to campaigning against the academy's construction were defeated.
Plaid's leadership succeeded in watering down a motion on the issue at the party's autumn conference in Llandudno that would have committed Plaid to opposing the scheme.
An amendment passed instead said the party "recognises the opposition within Plaid Cymru" to the project.