Tony's Blair's Labour government considered setting up a holding camp on the Isle of Mull in an attempt to drive down the numbers of asylum seekers entering in the UK, according to newly released official papers.

The plan, put forward by one of the prime minister's closest aides, was part of a "nuclear option" for tackling the asylum issue which would have seen illegal migrants put straight back on the plane they arrived on with little or no right of appeal.

Drawn up just months before the US-UK invasion of Iraq, the scheme also called for the creation of a series of regional "safe havens" in countries such as Turkey and South Africa - where refugees who could not be returned to their own country could be sent.

Although in the event it was not taken up, it echoes the debate still taking place more than 20 years later around Rishi Sunak's plans to deport asylum seekers to Rwanda.

The proposals, contained in files released by the National Archives in Kew, west London, reflect Mr Blair's frustration that "ever-tougher controls" in northern France had not had an impact on the number of asylum claims - which reached a new monthly high of 8,800 in October 2002.

"We must search out even more radical measures," Mr Blair scrawled in a handwritten note.

Following a brainstorming session with senior officials and advisers, the prime minister's chief of staff Jonathan Powell produced a paper entitled Asylum: The Nuclear Option, in which he questioned whether the UK needed an asylum system at all.

"As an island, people who come here by sea have by definition already passed through a safe country. And very few of those who apply at airports are genuine refugees," he wrote.

"So in fact what we should be looking at is a very simple system that immediately returns people who arrive here illegally. Uttering the word 'asylum' should not allow people to opt out of this system and give them the right to remain here for months or years while their cases are heard.

"Ideally we should not have an asylum hearing at all, simply a decision by an immigration officer to return someone followed by a one tier fast appeal against that decision if that is necessary."

Mr Powell said that it should form part of "a big bang solution that would send a shock through the system".

In particular, he pointed to the "great success" the Australians had had by housing all asylum seekers in one place, with many asking to be returned to their own country.

He said that officials in the office of the attorney general, Lord Goldsmith, had suggested setting up a camp on the Isle of Mull in the Inner Hebrides where people could be detained until they could be removed.

"I doubt that is going to work because of the nimby factor, but we have commissioned work to look at tagging, detention etc to help deter people and ensure we are able to return them as soon as their appeals have been heard," Mr Powell wrote.

Elsewhere, other officials suggested claimants could be sent to the Falkland Islands, 8,000 miles away in the south Atlantic.

Mr Powell said they were also looking at establishing a series of "safe havens" in Turkey, South African and Kenya - where asylum seekers from Iraq, Zimbabwe and Somalia could be returned to.

The Foreign Office said it believed Turkey in particular could be persuaded to set up such a centre "quite rapidly" in return for financial assistance, while the United Nations High Commissioner for Refugees would back such an approach.

Mr Powell said they should also legislate "incompatibly" with Article 3 of the European Convention on Human Rights to allow the removal people despite the risk of persecution - even though it would be challenged by the court in Strasbourg.

"We would like to extend this to return any illegal immigrant regardless of the risk that they might suffer human or degrading treatment," he advised.

"We would almost certainly lose this case when it got to Strasbourg. But we would have two to three years in the meantime when we could send a strong message into the system about our new tough stance.

"And we would make clear that if we lost in Strasbourg we would denounce the ECHR and immediately re-ratify with a reservation on Article 3."

Home Office lawyers warned that the measures would fall foul of the Geneva Convention on refugees.

An exasperated Mr Blair scrawled "just return them", adding: "This is precisely the point. We must not allow the ECHR to stop us dealing with it."