Feroz Abbasi and Moazzam Begg, two of the men being held at the high security detention centre in Cuba, are expected to be among the first of the suspects to face terrorism trials at US military tribunals.
“We will be discussing our reservations about the military commissions and the options of the detainees being returned to the UK,” an unidentified foreign office spokesman told Sky News.
Haynes and his team are scheduled to arrive in London on Tuesday, where they will meet with Attorney General Lord Goldsmith.
Lord Goldsmith has already visited the US twice and has secured an agreement that prosecutors will not press for the death penalty in the cases of two of the Britons.
The Britons are among 660 al-Qaida suspects due to go on trial.
Last month the mother of Abbasi begged the Government to bring him home for a fair hearing.
“I would say to the representatives taking part in this week’s discussions that justice requires a fair trial and British citizens should be removed from the legal black hole at Guantanamo Bay,” Solicitor Louise Christian, who is representing Zumrati Juma – mother of 23-year-old Feroz Abbasi – told Sky News.