Iraq's Government has warned Shiite cleric Moqtada al-Sadr that he would face a military strike within hours unless he ends his uprising, disarms his militia and quits a shrine Najaf.
In Baghdad, US troops have overrun his stronghold in the sprawling Shiite slum of Sadr City, meeting little resistance.
A spokesman for Sadr says he wants the Government to send a negotiator to work out details for ending the two-week crisis.
The crisis has dented the authority of interim Prime Minister Iyad Allawi, killed hundreds and rattled world oil markets.
"Moqtada requests a negotiator to agree on arrangements to implement the demands," spokesman Sheikh Ahmed al-Sheibani said.
Iraqi Minister of State Kasim Daoud says the Government has exhausted all peaceful means to persuade Sadr to back down.
He says it is determined to impose a military solution unless Sadr abandons violence, hands in weapons and leaves the Imam Ali Mosque.
He says Sadr is facing his "final hours" before an attack.
Mr Daoud vows to liberate the shrine, but declines to say whether the Government would storm the country's holiest Shiite site, where Sadr and his Mehdi militia are holed up.
Any assault could provoke outrage among Iraq's majority Shiite community, especially if US forces are involved.
Earlier in Najaf, explosions and sniper fire echoed around the city's holy sites.
