The father of a British detainee facing trial before a US military tribunal at Guantanamo Bay today called on Mr Blair to use his US visit to demand his son's return to Britain.
Mr Moazzam Begg (35) from Sparkbrook, Birmingham, was one of two British citizens named by US President George Bush on a list of six detainees to be tried for alleged links to al-Qaeda.
His father, Mr Azmat Begg, today insisted his son was innocent and accused the US authorities of denying him human rights during his 18-month captivity.
If Mr Blair could not secure his son's return to Britain for trial before a British court, Mr Begg said he was convinced his son would be executed by the Americans.
He told BBC Radio 4's Todayprogramme: "[Tony Blair] should assure the Americans that our system of justice is quite good and this country is the mother of the democratic world with the oldest legal system in the entire Western world, internationally accepted as a fair and objective legal system".
Reports have suggested British Home Secretary David Blunkett is reluctant to seek extradition of the Guantanamo Bay detainees because of fears there is insufficient evidence to charge them in a British court.
PA