The family of a law student detained at Guantanamo Bay are waiting to find out if the Government will be forced to help him.

Omar Deghayes, 36, from Saltdean, has been imprisoned at the US military base in Cuba since his arrest in Pakistan in 2002.

Last month, a top law firm lodged a claim for judicial review of the decision taken by the Home and Foreign Secretaries not to pressure the US for the return of three British residents held prisoner there.

Government solicitors were due to respond to Birnberg Peirce and Partners' claim on Friday but their deadline has been extended to Wednesday.

Once they have responded a judge will decide whether the review can proceed.

Birnberg Peirce hopes the court will rule that the Home and Foreign Secretaries have a duty to demand the recall of Omar and the other non-national British residents held without trial as terror suspects.

The firm claims the men and their families should expect the UK Government to respect their human rights because it has signed up to international human rights and anti-torture treaties.

It also says the Government is discriminating against the British residents on the grounds of their nationality, because it earlier made a successful demand for the return of British nationals.

Firm partner Gareth Peirce is one of Britain's best-known civil rights lawyers and is currently representing the family of Jean Charles de Menezes, the Brazilian shot dead on the Tube by police who believed he was a terrorist.

Campaigners for Omar are holding a national demonstration outside the American Embassy in London on Saturday, January 21. Former Labour MP Tony Benn, Omar's sister Amani and his lawyer Clive Stafford Smith will all speak at the protest.

Thousands of people from across the country are expected to attend. Protesters will meet at Tothill Street off Parliament Square at noon and march up Whitehall to the US Embassy.

Coach tickets from Brighton (£6/£4) are on sale, call Jackie on 07796 478421.

Visit www.save-omar.org.uk for more information.