CAIRO (AFP) - Tens of thousands of protesters rallied in Cairo on Friday as the opposition piled pressure on President Mohamed Mursi after a panel rushed through a draft constitution seen as undermining basic freedoms.

“Down with the constitutional assembly,” vast crowds armed with megaphones chanted as they filed into Tahrir Square, the epicentre the uprising that overthrew Hosni Mubarak in early 2011.

Banners condemned “dictatorial Mursi” while protesters shouted “down with the rule of the Guide,” a reference to the leader of the Muslim Brotherhood movement, through whose ranks Mursi rose before becoming president.

The marches, led by opposition figures, set off from several Cairo districts early in the day to join the protesters in the square.

The Islamist-dominated assembly, tasked with drafting a new charter to replace the one suspended after Mubarak’s ouster, approved the draft early on Friday after an almost 24 hour-long session boycotted by liberals and Christians.

The panel’s head, Hossam el-Ghiriani, said a delegation from the Constituent Assembly would visit Mursi on Saturday to present him the draft constitution. Mursi is expected to call for a referendum within two weeks.

Rights activists say the charter undermines freedoms of women and religious minorities while the opposition says it was rushed through to force an early referendum.

The constitution has taken centre stage in the country’s worst political crisis since Mursi’s election in June, squaring largely Islamist forces against liberal opposition groups.

The crisis was sparked when Mursi issued a decree on November 22 giving himself sweeping powers and placing his decisions beyond judicial review. His decree prevented the constitutional court from ruling on the constituent assembly’s legality, as it was meant to do on Sunday. A court had disbanded an earlier panel.

A coalition of leading dissidents formed in protest at the decree has warned that an ongoing judicial strike could escalate into mass civil disobedience.

The strike, called by the top Cassation Court and several other tribunals to protest the decree, could place the referendum in jeopardy, if judges who normally supervise elections refuse to grant it legitimacy.

Rights activists have lambasted the draft charter, with Human Rights Watch saying it “protects some rights but undermines others”.

“Rushing through a draft while serious concerns about key rights protections remain unaddressed will create huge problems down the road that won’t be easy to fix,” the US organisation’s Middle East director Joe Stork said in a statement.

The document retained a vague Mubarak-era constitution article stating that the “principles of Islamic law” are the main source of legislation. But it added a new provision stipulating that the principles of Islamic law were to be interpreted according to the tenets of Sunni Islamic rulings, a clause Christian churches have opposed.

The draft also allows that state a role in “protecting ethics and morals” and bans “insulting humans,” which rights activists say could censor political criticism of the president.

Nobel Laureate and opposition leader Mohamed ElBaradei slammed it, saying “it’s fate will be the dustbin of history” in a television interview.

Several private newspapers announced that they would not appear on the street next Tuesday to protest what they consider to be a lack of press guarantees in the new charter.

Abdallah Sennawi, a member of the Committee to Defend Freedom of Expression and Thought, said private television channels would follow suit on Wednesday.

In a pre-recorded interview broadcast on Thursday night, Mursi repeated that his new powers, in which he can make decisions beyond judicial review, will expire once the constitution is ratified.