The formal campaign for Scottish independence has been launched at a celebrity-endorsed event.

Organisers of the Yes Scotland movement vowed to stage the "biggest community-based campaign in Scotland's history" in the run-up to the independence referendum which could take place in October 2014.

First Minister Alex Salmond, one of the key speakers at the launch in Edinburgh, said: "We unite behind a declaration of self-evident truth.

"The people who live in Scotland are best placed to make the decisions that affect Scotland.

"We want a Scotland that's greener, that's fairer and more prosperous.

"We realise that the power of an independent Scotland is necessary to achieve these great ends."

The "yes" campaign for independence wants one million Scots to sign a declaration of support by the time of the referendum in the autumn of 2014.

Mr Salmond was joined by politicians from other parties, including the Greens, who want Scotland to leave the UK.

A message of support from actor Sir Sean Connery, a long-standing supporter of independence, was read out to the crowd.

Alan Cumming, the Scottish film, television and stage actor, also attended.

Mr Salmond continued: "We don't start from scratch. We have a parliament which has earned its spurs for more than a decade. If the parliament can run education, then why can't it run the economy? If it can be trusted to run the health service, then why can't it represent Scotland internationally?

"If it can be trusted to protect our old people, then why can't we protect the country, and do so without the obscenity of nuclear weapons?"

After a round of applause, the SNP leader said: "I want Scotland to be independent not because I think we are better than any other country but because I know we're as good as any other country.

"Like these other nations, our future, our resources, our success should be in our own hands."

The campaign will be built "brick by brick" across communities, he said.

"We intend to take our case to the people by community activism and online wizardry," he said.

The message from former James Bond star Sir Sean was read out by Martin Compston, who starred in the Ken Loach film Sweet Sixteen.

"This is a historic day for Scotland," it said. "The Yes campaign has centred on a positive vision for Scotland. It is rooted in inclusiveness, equality and that core democratic value that the people of Scotland are the best guardians of their own future."

The SNP played a leading role in the "Yes Scotland" campaign, which was launched at Cineworld in Edinburgh and included other parties, celebrities and businesses.

There have been some concerns campaigning is starting too early with a referendum not likely until 2014.