Bassem Sharif, spokesman of the Fadila party, said on Friday: "This afternoon at 4pm (1200 GMT) the seven heads of Shia parties within the alliance will meet the president to discuss the issue of prime minister."
The Fadila Party is one of the factions in the Shia United Iraq Alliance that is set to lead the new government.
Sharif said the meeting would also address the selection of Iraq's president and two vice presidents and the speaker of the parliament.
"The meeting has been arranged to expedite political
negotiations before parliament opens Monday," Sharif told AFP.
Dhafer al-Ani, spokesman of the National Concord Front, the leading Sunni Arab faction, confirmed that Jalal Talabani, the president who is himself a Kurdish politician, would be meeting only Shia leaders.
"We are meeting nobody today, but our brothers the Shia leaders are meeting the president later today and will discuss with him some essential issues regarding the current political situation in Iraq," he told Aljazeera.net.
"We believe the meeting will discuss arrangements for Monday's parliament meeting," he said.
Four months after elections to the first full-term parliament since the 2003 invasion, Iraq is struggling to put together a national unity government against a background of widespread Kurdish and Sunni opposition to al-Jaafari's candidacy as prime minister.
But al-Dawa party leader has refused to step down and wants his fate to be decided by MPs.
Adnan al-Pachachi, Parliament's acting speaker, announced earlier this week that the assembly would convene on Monday.