An "indeterminate period" of unilateral nuclear disarmament could be imposed on the UK if Scotland becomes independent, according to a Westminster committee.
The UK's Trident nuclear weapons are entirely based and serviced in Scotland, and the SNP has committed to their removal if the country returns a Yes vote in the 2014 referendum.
In a new report, the UK Parliament's Scottish Affairs Committee says the UK and Scottish governments must "fully detail the consequences of the removal of Trident as part of the whole secession agreement as soon as is practical".
The referendum should not go ahead without establishing the full consequences for defence and the UK's "nuclear deterrent" beforehand, the committee has said. Nuclear weapons in Scotland could be disarmed within days and removed within months, while the construction of facilities elsewhere in the UK could take upwards of 20 years, the committee heard during its evidence gathering.
The committee has outlined several possible options for future arrangements, including relocating outside the British Isles and an agreement to allow the UK to continue to operate Trident out of the Clyde.
Committee chair Ian Davidson said: "A separate Scotland would be presented with a choice over Trident. It could honour the long-standing commitment of the SNP that there should be no nuclear weapons in Scotland and insist on the 'speediest safe transition' of Trident from Scotland.
"Alternatively, a separate Scotland could allow Trident to remain on the Clyde long enough for the UK to identify and develop a new base elsewhere. This option would mean armed nuclear submarines operating out of Scotland for 20 years or longer. Developing a new base, particularly replicating the facilities at Coulport, could only be done at great expense and the UK Government has made it clear that any such costs would be included in the separation negotiations.
"This would have to be alongside other items such as access to intelligence and the work of the Government Communications Headquarters and, beyond defence, retaining the Bank of England as a lender of last resort and financial regulator for Scotland."
SNP MSP Bill Kidd welcomed the report, saying its findings can "only enhance the case for an independent Scotland where we can move forward towards a country free from Trident nuclear weapons".
The Nationalist, who is a member of the Council of Parliamentarians for Nuclear Non-proliferation and Disarmament, said: "Trident is not wanted in Scotland and never has been, yet the UK Government are proposing to waste £100 billion dumping another generation of Trident nuclear weapons on the River Clyde. With independence, we can ensure that Scotland's share of the money wasted on Trident is diverted to building a stronger and fairer society."