Scotland's international partnerships would remain unchanged in the event of independence, the First Minister has told an American audience.

Alex Salmond said the nation's alliances with the US and other nations would endure while Scotland would become an independent and active member of organisations, ranging from the European Union and the United Nations to Nato.

The First Minister was giving a speech at the public policy organisation the Brookings Institution in Washington DC as part of a visit to the US to strengthen economic links, discuss Scotland's constitutional future and mark the friendship between the two countries.

Mr Salmond told his audience that the SNP's policy to join Nato demonstrated its commitment to working closely with its allies, although he restated the requirement for the nuclear weapon Trident to be removed from Scotland as soon as possible.

The SNP voted to change its position on Nato membership at its conference last year.

"It could be argued that membership of Partnership for Peace would enable us to fulfil many of our defence requirements as does Ireland and Finland," the First Minister said.

"But we understand why, in the international community, countries such as Iceland, Denmark, Norway, and indeed the USA - would prefer it if we signalled our intention to be part of the Nato Alliance as an independent country.

"Such a step would demonstrate clearly our commitment to working closely with those friends and allies.

"We should acknowledge that Nato is a cornerstone of defence policy for these nations and therefore membership is a responsible decision for Scotland to seek."

The First Minister, who has been vocal in his opposition to the war in Iraq, said Scotland would fulfil Nato commitments to collective self-defence, but its participation in "either in peace-keeping or military operations would be on the basis of legitimacy".

"I have recently argued that an independent Scotland should have a written constitution," he said.

"In my view, that constitution should include safeguards on the circumstances under which we commit our armed forces to theatres of conflict- such as a requirement that military action is in accordance with the United Nations Charter."

Mr Salmond went on to say that continued hosting of nuclear weapons in Scotland would be "absurd".

"We recognise that the safe removal of the UK's Trident system would require careful discussion with the UK Government and our Nato allies," he said.

"But our aim would be clear - we would require the speediest but safest removal of Trident from our shores."

He also hinted at a future role for Scotland in peace-keeping efforts.

"An independent Scotland would not be a global superpower, " he said. "But we would be a good global citizen.

"Scotland is in an excellent position to assist peace and reconciliation efforts. In recent years we have already hosted important discussions such as those that led to the 2006 St Andrews Agreement, which helped progress devolved government in Northern Ireland."