The Muslim Brotherhood called on Sunday for staging massive rallies in front of its headquarters in support of President Mohamed Mursi's new constitutional decree issued on Saturday.
The decree was issued after a "national dialogue" that was boycotted by main figures of the opposition.
The new decree cancelled a decree Mursi issued on November 22 which expanded his powers and shielded his decisions from judicial oversight.
However it shielded itself and other constitutional declarations from court challenges - so, while the president's decisions can now be appealed, his constitutional decrees cannot.
It also outlined measures to take if the people were to vote against a draft constitution written by an Islamist-dominated assembly, in a December 15 referendum.
"The new decree reflects the keenness of the president on the best interest of the country as he refuses to put restrictions on the dialogue... so that it expresses the free will of political forces who are genuinely seeking ways out of the current crisis", said the Freedom and Justice Party lawyer Abdel Moenem Abdel Maksoud as reported by the Middle East News Agency.
Abdel Maksoud stressed that the primary purpose of the president's decisions is to "achieve security and stability and put Egypt on the road to real renaissance."
He added that the president is working on establishing a "state of institutions" ruled by a constitution that separates powers and called on everyone to put aside their personal interests and focus on national interests.