ElBaradei returned to a warm welcome in February after leaving his post at the head of the U.N.'s International Atomic Energy Agency, lending to speculation he would challenge Egyptian President Hosni Mubarak in 2011 elections.
He was ignored, however, by Egypt's main opposition party the Muslim Brotherhood in calling for a boycott of parliamentary elections in November. The ruling National Democratic Party, however, swept the polls amid accusations of ballot tampering.
The Muslim Brotherhood said through its Ikhwanweb site that "differences in ideology" were set aside in a weekend meeting with members of ElBaradei's National Association for Change and other Egyptian opposition parties.
ElBaradei told opposition leaders that it was time to unite in the spirit of political reform. In a 12-minute video posted on his Facebook page last week, ElBaradei said he was focused on a campaign of civil disobedience for 2011.
Muslim Brotherhood officials said they were always reaching out to potential reformers as the next election season approaches.
Brotherhood officials added that they were advocating "a civil state governed by Islamic references."