15 political parties and groups have called on their supporters to protest against what they see as President Mohamed Morsi's new constitutional declaration that shields his decisions from judicial oversight and deems the Islamist-dominated Constituent Assembly immune from dissolution by courts.

Parties and groups who announced the call for Tuesday are also staging a sit-in in Tahrir Square, where tens of thousands demonstrated Friday in protest against Morsi's decree.

The groups include the liberal Constitution Party, leftist Popular Current, Socialist Popular Alliance Party, 6th of April, liberal Free Egyptians Party, liberal Egyptian Social Democratic Party, Youth for Justice and Freedom group, Kefaya movement, the National Front for Justice Democracy and Maspero Youth Union.

"We are facing a historic moment in which we either complete our revolution or we abandon it to become prey for a group that has put its narrow party interests above the national interest," said the statement, issued by the liberal Constitution Party (Dostour Party), led by reform campaigner Mohamed El-Baradei, on its Facebook page late Friday.

In a speech Friday to thousands of supporters, Morsi said that he does not want to abuse his legislative power, adding that he would never use his authorities against any person or party.

“The Constitutional Declaration does not aim to exact revenge on anyone," Morsi said, adding that it is the opposition's right to express their discontent with the constitutional document.

Three main planned marches are slated for Tuesday, to start at 5.00pm from areas of Ramsis, Shubra and Mohandessin around central Cairo, where they will all meet in Tahrir Square.

Over 30 parties and groups participated in Friday's demonstrations, including those who are calling for Tuesday's marches.

The newly-announced constitutional declaration stops courts from challenging Morsi's decisions until the new constitution is passed. The decree also grants immunity to the Shura Council (upper house) and the controversial Islamist-led constituent assembly from dissolution by court orders.