Three British residents held by the US at Guantanamo Bay were yesterday given the go-ahead to seek a High Court order requiring Foreign Secretary Jack Straw to petition for their release.

A judge in London said allegations of torture being practised at the detention camp in Cuba meant the prisoners, and their families living in the UK, had an arguable case that the British Government was under an obligation to act on their behalf.

Mr Justice Collins stressed his decision was "no guarantee" that the three men, Bisher al-Rawi, Jamil el-Banna and Omar Deghayes, and their families, would win their case - there were formidable arguments against it.

The judge's decision came after a day-long hearing during which he commented that America's idea of what constituted torture "is not the same as ours and doesn't appear to coincide with that of most civilised countries".

His remarks coincided with a UN report which urged that the Guantanamo camp should be shut down, and called on the US Government to refrain from any practice "amounting to torture or cruel, inhuman or degrading treatment".

The case against Mr Straw is expected to be heard in full in mid-March.

The men's solicitor, Gareth Peirce, said after yesterday's hearing: "After so many years of such bitter disappointment, this is the first ray of light that we have had - the first ability to hope that this might be the beginning of the end for the ordeal of these three families."

The Government's counsel, Philip Sales, said the Foreign Secretary had already decided to reconsider Mr al-Rawi's case because of its particular circumstances. But he argued that permission should not be granted in the other cases because the detainees did not have British nationality.

There are thought to be about 500 people held at the centre at a US naval base in Cuba. None are British but Amnesty International believes eight have previously been resident in the UK and some have relatives here.

US-based British human rights lawyer Clive Stafford-Smith said of yesterday's UN report: "This is another authoritative body speaking and it's absolutely right - they should shut the place down.

"The question now is whether the Bush Administration are going to listen or do what we have always seen and bluster against the UN.

"The UN mentions in their report the coercive and violent way the US military is force-feeding people."

Mr Stafford-Smith said he had witnessed that when he went to see a client. "He had a 43-inch tube up his nose which he pulled out in an excruciating way. He told me they had beaten him up to force feed him."

Last night, the White House rejected the UN report.

"These are dangerous terrorists that we're talking about that are there," said spokesman Scott McClellan.

He dismissed the UN report as "a rehash" of allegations that have been made previously by lawyers for some Guantanamo prisoners.