Mr Fox says UK defence policy needs "wholesale" review
UK troops could be withdrawn from Germany if the Tories win power, the shadow defence secretary has said.
Liam Fox said maintaining the current presence of more than 20,000 was "no longer necessary".
Other Nato member states should take up the UK's responsibilities in Germany, allowing British troops to deploy elsewhere, he told the Daily Telegraph.
The Ministry of Defence says the number of forces personnel in Germany has fallen and is under constant review.
"Following the Cold War, we've drawn down our troops in Germany to reflect the changed strategic context. The UK always looks to share responsibility proportionally among its Nato allies," a spokesman said.
Ministers have previously said they intend to "continue the long-term basing" of heavy armour in Germany.
Much of the British presence is centred on Herford, near Hanover in the north, where the 1st Armoured Division is based.
The region's wide plains allow for tank training which is barely possible in the UK. Estimates have suggested it could cost up to £5bn to relocate all the British troops in Germany to home bases.
However, Mr Fox signalled his determination to conduct a "wholesale recasting of our foreign and defence policy" in the newspaper interview.
He wants a "more creative diplomatic solution" in Nato involving new member states from eastern and central Europe, particularly Poland, taking over Britain's commitments.
"What is not possible is for Britain to try to do everything. We need some change," he said.
"If other countries are willing to take up roles in continental defence that leaves Britain and France able to take on expeditionary roles."
"Much as people regard it as a great political sport to be constantly berating our allies on what they do and don't do in Afghanistan, it's more important that we have more effective burden sharing so we can be freed up from some responsibilities."
There were constitutional and political reasons why some Nato countries were unable to do the same amount when it came to expeditionary warfare, said Mr Fox.
A final decision would depend on negotiations with Nato allies, in particular France, and on the Ministry of Defence's ability to handle the return of so many soldiers for whom there is no accommodation in the UK.
Mr Fox accepts a plan already exists to gradually reduce troop levels in Germany and that it would be a "long-term process".
Generations of soldiers and their families have passed through Germany, although the presence has been reduced from 150,000 when the Nazi regime fell in 1945.
By 1957, 55,000 remained as Western allies provided protection against a potential invasion from the Communist states of the Eastern bloc.
Even after the Cold War ended, Germany was keen to retain the British military and their families who are estimated to contribute about 1.5bn euros to the economy.
Mr Fox said he had told civil servants to prepare plans for cutting the department's administrative costs by 25% - some £3bn - by 2012.
He also confirmed that Gen Sir Richard Dannatt, the former head of the Army, had been offered a peerage but would not be a minister in any Conservative administration.