Judges in Egypt's appeal courts have called a strike in protest at President Mohammed Mursi's recent decree giving himself new powers.
The decree, issued last Thursday, gave Mr Mursi powers to take any measures to protect the revolution, and stated that no court could overturn his decisions.
The move sparked widespread protests.
Meanwhile, the assembly drafting a new Egyptian constitution is expected to vote on a draft on Thursday, officials have said.
"Tomorrow [Thursday] will be a great day," said the head of the Islamist-dominated assembly, Hossam al-Gheriani.
He urged the non-Islamist parties, the syndicate of journalists and Egyptian churches - who walked out of the assembly last week - to return.
Once adopted by the assembly, the proposed constitution will then be put to a national referendum.
'Protecting the revolution'
The Muslim Brotherhood and other Islamist groups have called a rally for Saturday in support of Mr Mursi.
His backers say the decree was needed to protect the gains of the revolution against a judiciary with deep ties to overthrown President Hosni Mubarak.
Appeals courts and the Court of Cassation will halt work until the decree is revoked, the judges say.
On Monday, Mr Mursi sought to defuse the crisis by saying the decree granting him new powers was limited in scope.
He met senior judges and told them that the measure would be restricted to "sovereign matters" designed to protect institutions.
But judges who attended the meeting said they were not satisfied. They want him to withdraw the measure completely.
Protesters who have taken to the streets since the decree was issued last Thursday say Mr Mursi's Muslim Brotherhood has hijacked the revolution.
The Constitutional Court - which is not taking part in the strike - has accused Mr Mursi and the Muslim Brotherhood of seeking revenge for an earlier decision in which the court dissolved parliament.
The BBC's Jon Leyne, in Cairo, says the aim of Thursday's vote on the draft constitution could be to pre-empt a Constitutional Court ruling on Sunday which may once again dissolve the assembly.
Publishing a constitution in these circumstances would be a deeply inflammatory move, our correspondent says.
Many Egyptians are suspicious that the assembly, dominated by the Muslim Brotherhood and other Islamists, wants to impose a constitution that increases the role of Islam in Egypt's government and public life.
Anti-Mursi protests were held in Cairo, Alexandria, Suez, Minya and other Nile Delta cities on Tuesday.
Low-level rallies continued in Cairo's Tahrir Square on Wednesday. The Brotherhood has organised counter-demonstrations, including one in Egypt's second city, Alexandria, which attracted several thousand participants.
The decree bars judges from dissolving the assembly that is drawing up a new constitution.
The president is also authorised to take any measures to preserve the revolution, national unity or safeguard national security.
Critics say the decree is an attack on the judiciary.