After two months of quiet under Egypt's new military junta, the Muslim Botherhood said it will rejoin demonstrations on Friday, the Wall Street Journal reports.

The move could reinvigorate Egypt's revolutionary movement, which subsided after protesters ousted President Hosni Mubarak in February.

Muslim Brotherhood members say the group will throw its official weight behind demonstrations against the country's provisional military leadership, which protest leaders complain has been too slow to purge and prosecute lingering elements of Mubarak's regime.

The Brotherhood's participation in Friday's protests amplifies the down-played tensions between the military and Islamist politicians, whose support thus far has created the necessary political ballast for the military's sudden assumption of rulership.

Observers suggest the 83 year-old Islamic movement wants to bolster its revolutionary mystique ahead of September's elections by joining Fridays' protests aimed at pressuring the military to purge what is left of ex-President Hosni Mubarak's National Democratic Party

"I think they're afraid of losing momentum," Revolutionary Youth Union member Abdullah Helmy told the WSJ. "Whatever you protest for at this time, the most political gain is for parliamentary elections. They are preparing themselves on the ground for the real battle."

The Brotherhood's return to Tahrir Square, the symbolic epicenter of Egypt's protest movement, may also be designed to deal with internal dissent among its younger, more radical members. Younger members of the Brotherhood have openly criticized the group's top-down leadership structure and its leaders perceived timidity in challenging the ruling junta.

"The youth don't like the guidance bureau's decisions," said Ibrahim al Zaafarani, a prominent member of the Brotherhood before he resigned last week to form his own youth-oriented Islamist party. "They are still strongly committed, but they are definitely not satisfied."

In a rare public spat for the secretive organization, Brotherhood youth called a press conference and demanded more democracy within the organization. Prominent members, including Zafaarani and Abdel Moneim Abdul Fotouh, openly criticized the Brotherhood's draconian rules. Both men have said they will start their own political parties.

"We have different opinions which are now louder after this freedom wave," said Mohsen Rady, a member of the Brotherhood's parliamentary bloc until he lost his seat in December elections, who sought to play down the rift in the group. "The desire to participate [on Friday] was not the desire of the youth. It was not a response to a youth demand. This is a social, national responsibility, which we believe is crucial."