Lawyers for Nour, leader of the opposition al-Ghad (Tomorrow) Party, said on Thursday an acquittal was more likely now that party worker Ayman Ismail Hussain has retracted his plea.
Nour's supporters say the authorities have put Nour on trial to disrupt the politician's plan to challenge President Hosni Mubarak in September presidential elections.
He and six others face charges of submitting forged signatures when the party applied for recognition last year.
"I confessed to forgery under pressure from officers from state security," Hussain said after his lawyer told the court he had changed his plea to not guilty.
At the first session of the trial on Tuesday, Nour pleaded not guilty while five others, including Ismail, entered guilty pleas.
Another defendant is being tried in absentia.
Civil disobedience call
Egypt's opposition Muslim Brotherhood movement has called for nationwide civil disobedience as a means of increasing pressure on President Hosni Mubarak to end his 24-year rule.
The banned but tolerated group made the call on Thursday during an inaugural meeting of the National Alliance for Reform and Change (NARC), a grouping of activists of various political persuasions united in their desire to see Mubarak step down.
The Muslim Brotherhood had invited all of the country's political forces to join the newly formed alliance, but only the centre-right Wafd party sent a representative to the event attended by about 1000 activists.
Muslim Brotherhood staged a
series of protests
"The Wafd party is honoured to join this alliance," party delegate Mohammed Alwan told participants. He added that his party supported the Muslim Brotherhood's call for civil disobedience to force Mubarak out of office.
"We are not weak, but the government is exploiting our differences," said Magdy Hussein, former editor of the banned Al-Shaab newspaper, mouthpiece of the Islamist-oriented Labour party.
The weight of the new alliance remains limited, with only 19 MPs in the 454-seat parliament, four of them from the legal Wafd party.
The remaining 15 are part of the bloc controlled by the banned Muslim Brotherhood but all of them entered the house as independents, including the only deputy from the Labour party, whose activities have been suspended.
Nasserist activist and founder of the still unregistered Al-Karama party, Hamdeen Sabahi, said he sympathised with the Muslim Brotherhood initiative, although he declined to be part of the new movement.
"The Brothers are the big force that the Egyptian street is in dire need of," he said.
"I confessed to forgery under pressure from officers from state security"
Ayman Ismail Hussain,
al-Ghad Party worker
The meeting was chaired by the Muslim Brotherhood's deputy supreme guide Mohammed Habib.
Hundreds of Muslim Brotherhood supporters were arrested during a May crackdown that followed a wave of street protests. Most of them have since been released.
Habib said the new alliance would have a general secretariat and committees.
The 77-year-old Mubarak has yet to announce if he will seek a fifth six-year term in elections scheduled for September, Egypt's first contested presidential polls.