The senator accused opposition leaders of muckraking.
The main opposition leaders have been arrested or under house arrest.
State television reported that President Saleh would only sign it in the presence of opposition leaders.
The main opposition leaders had been arrested or placed under house arrest.
Syrian and Egyptian activists have prevented Syrian opposition leaders from meeting the Arab League in Cairo, accusing them of treachery.
The interim regime unites 14 opposition leaders from different parties, including past prime ministers, ministers and speakers of parliament.
Former presidents Akbar Hashemi Rafsanjani and Mahmoud Khatami did not attend the event, which was also boycotted by opposition leaders Mir Hossein Moussavi and Mehdi Karroubi.
Senior officers have had regular meetings with a range of opposition leaders, and at their urging removed the last prime minister appointed by Mr Mubarak.
Perez said the challenge is for all opposition leaders to be prepared to work with the government and Socialist lawmakers to help the country.
A prominent Yemeni journalist, Nasser Arrabyee, says the opposition leaders are saying one thing in the street and another behind closed doors.
First, he had almost all the country's opposition leaders arrested by the morning of April 7th, which left the protesting crowds without any sense of direction or moderating influence.
Earlier, Syrian opposition leaders repeated a demand for President Bashar al-Assad to leave power, saying they will not agree to the talks without a timetable for his withdrawal.
