Moazzam Begg and Feroz Abassi are among those still held in Guantanamo

US military papers state the men will face Combatant Status Review Tribunals by mid-October, the Guardian said.

The Pentagon says suspects deemed enemy combatants, not prisoners of war, can be held indefinitely without charges.

The UK Foreign Office said it could not confirm the time frame of the tribunals but would monitor progress.

The tribunals follow a Supreme Court ruling enabling inmates to challenge their detention through the US legal system.

Because they don't constitute trials as such the existence of them does nothing to change our position Foreign Office spokeswoman

The hearings involve panels of three officers charged with deciding whether individuals have been classified correctly as "enemy combatants".

Detainees can testify and request affidavits from witnesses during the tribunals, but instead of a defence lawyer are represented by a military officer.

A Foreign Office spokeswoman told BBC News Online: "All detainees are subjected to these CSRTs but we're not in a position to say when individual hearings will take place."

"Because they don't constitute trials as such the existence of them does nothing to change our position: in the absence of a fair trial in the US [the British detainees] should be returned home."

'Mangled process'

The director of campaign group Fair Trials Abroad, Stephen Jakobi, told BBC News Online he thought it was unlikely the Britons' would face tribunals in October.

"I don't think they want to put Britons through this mangled process until after the US election," he said.

Mr Jakobi added reports of the Britons' hearing dates followed news US troops in Afghanistan had killed a suspected Taleban commander earlier released from Guantanamo Bay.

He condemned the release of an "extremely dangerous guerrilla" while the four Britons remained in captivity as an insult to the UK government.

"It's a continuing slap in the face for the British government and the British people - it's not envisaged they'll give the Britons a fair trial or release them."

Feroz Abbasi, 23, Richard Belmar, 23, and Martin Mubanga, 29, all from London, as well as Moazzam Begg, 36, from Birmingham are still being held at the US base in Cuba.