(CNN) -- A top Egyptian opposition leader Saturday urged a boycott of parliamentary elections in April, describing them as "an act of deception."
Mohamed ElBaradei is one of the leaders of Egypt's National Salvation Front, a coalition of opposition groups.
In a tweet from his official account, he called for the boycott, just like he did three years ago.
"Called for parliamentary election boycott in 2010 to expose sham democracy. Today I repeat my call, will not be part of an act of deception," it read.
But Essam Erian, a senior member of the Muslim Brotherhood's Freedom and Justice Party and leader of the majority party in Egypt's upper house of Parliament, criticized the proposed boycott.
"Evading a popular test [by not participating in the parliamentary elections] only means that some people want to assume the executive powers without a democratic mandate," Erian said on the party's Facebook page.
"Participation [in the upcoming elections] is the best choice for any politician who has any popular support. Because if he or she has a popular majority then this will be reflected in majority wins or seats won that can translate into participation in the executive branch or remaining in Parliament as an opposition force," Erian said.
On Saturday, Egypt changed the series of dates for the country's parliamentary elections in several areas to accommodate Coptic Christians and their Easter celebrations, state-run Middle East News Agency reported. President Mohamed Morsy decreed the changes, the agency said.
The first stage of the elections will be held April 22-23 instead of April 27-28 in the governorates of Cairo, Behaira, Minya, Port Said and Northern Sinai.
The second stage will be held on May 11-12 instead of May 15-16 in Giza, Alexandria, Sohaj, Bani Swaif, Aswan, Suez, Red Sea and New Valley. The runoff will be held May 19-20 instead of May 22 and 23 in those areas, the agency said.
The third stage will be held May 28-29 instead of June 2-3 in Daqahliya, Qalyubia, Monufia, Qena, Damietta, Luxor, Matrouh and South Sinai. The runoff will be held on June 5-6 instead of June 9-10.
The fourth stage will be held on June 15-16 instead of June 19-20 in Sharqia, Gharbia, Assiut, Kafr el-Sheikh, Fayoum and Ismailia. The runoff will be held on June 23-24 instead of June 26 and 27.
The House of Representatives, the lower house in Egypt's bicameral system, will hold its first session July 2 instead of July 6, the agency said.
The elections will be the first since Egypt's highest court dissolved the lower house of parliament in June, and it will be the first full Parliament in Morsy's presidency. The upper house, the Shura Council, has continued to meet.
In the past year, violent clashes in Port Said, a coastal province along the Suez Canal, have highlighted the longstanding resentment residents there feel toward Cairo.
Previous elections have been held in three stages, rather than four.
On Friday, ElBaradei tweeted: Morsy's "decision to go for parliamentary elections amidst severe societal polarization & eroding state authority is a recipe for disaster."
ElBaradei headed the International Atomic Energy Agency, the U.N. nuclear watchdog, from 1997 to 2009. He also ran unsuccessfully in Egypt's presidential election last year.
CNN's Amir Ahmed contributed to this report.