Egypt will announce the official results of a vote on its new constitution tomorrow in a step which paves the way for the formation of a new parliament in about two months.
The creation of a new constitution is a vital step in Egypt's transition to democracy almost two years after the fall of military-backed strongman Hosni Mubarak.
But the opposition says the text, crafted mostly by President Mohammed Mursi's Islamist allies, fails to guarantee personal freedom and the rights of women and minorities.
It says it will lead to more trouble in the most populous Arab nation.
Unofficial tallies from the Muslim Brotherhood - which catapulted Mr Mursi into the presidency this year - indicated that 64% had approved the charter. An opposition tally had a similar result.
"The Supreme Elections Committee will announce on Tuesday at 7pm (5pm Irish time) the results of the referendum on the new constitution," judge Samir Abu el-Matti told state radio and TV today.
Mr Matti also said that the committee, which is led by judges, had spent the last two days investigating opposition and rights' groups accusations of voting fraud.
Mr Mursi's critics said the vote, conducted in two stages in a process that ended on Saturday, had been marred by a litany of irregularities, and have demanded a full inquiry.
The opposition, a loose alliance of socialists, liberal-minded Muslims and Christians, have also noted that less than a third of those eligible turned out to vote, undermining the legitimacy of the new constitution.