By Malcolm Brabant
BBC News, Cairo
Ayman Nour has been held in an Egyptian jail since January
Party of Tomorrow leader Mr Nour is regarded as a potential presidential candidate.
But his continued imprisonment is damaging his chances of running against President Hosni Mubarak later in 2005.
Mr Nour has been held in custody since the end of January.
He was arrested on allegations that he forged documents used to secure legal status for his Party of Tomorrow which was formed last autumn.
His wife Gamila Ismail believes the Egyptian authorities are trying to frame him.
Accusing him of forging petitions, this is just crazy, it is nonsense. He didn't have any reason to do this
Gamila Ismail, Nour's wife
Ms Ismail says that when security officers checked their penthouse in the expensive district of Zamalek, they were particularly interested in his tobacco boxes and medication.
"The lawyers explained to me later on that they were trying to find something illegal such as drugs."
The United States, which is trying to force the Arab world to become more democratic, has expressed deep concern about Mr Nour's continued detention.
Secretary of State Condoleezza Rice has told her Egyptian counterpart that she hopes "the issue is resolved soon".
Egyptian officials resent what they perceive as American interference in what they insist is a legal, not political matter.
Nour supporters' main demand is greater democracy
"Each and every one of us resists any foreign interference."
Last October the Nours and their supporters were celebrating the inauguration of their liberal, secular party.
The Party of Tomorrow's most important demand is for greater democracy.
Ayman Nour told me in October: "We love and appreciate President Mubarak, but we love this nation as well and would like it to develop like other countries."
Ayman Nour is really a very clever political animal. He might get 20% or 30% of the vote
Mustafa Kamel al-Sayed
But 25 years of political stagnation have left the Egyptian opposition struggling to find a candidate of sufficient stature and charisma to stand against Mr Mubarak.
Some analysts believe that Ayman Nour, a former journalist, lawyer and publisher, possesses the necessary profile to make substantial inroads against the president.
Mustafa Kamel al-Sayed, a Professor of Political Science at Cairo University, says: "Ayman Nour is really a very clever political animal.
"He might get 20% or 30% of the vote. But it is this perception that he might be capable of getting a large number of votes that would get the government to try to deprive him of this opportunity of running as a presidential candidate."
Rumours surface daily in Cairo that Mr Nour is going to be released soon.
Could this signal the end of Egypt's 25 years of political stagnation?
Ms Ibrahim fears that even if her husband is freed, he will be charged so that a trial hangs over his head and discredits him at election time.
"Accusing him of forging petitions, this is just crazy, it is nonsense. He didn't have any reason to do this," she says.
The case of Ayman Nour is being seen by many analysts as a true test of President Mubarak's commitment to greater democracy.
The challenge for Egypt is to protect its stability, while easing what Mr Mubarak's critics regard as some of the country's more authoritarian tendencies.