BAGHDAD, Iraq (CNN) -- Anti-U.S. Shiite cleric Muqtada al-Sadr's movement is "ready for all options" in a growing confrontation between his followers and the government of Prime Minister Nuri al-Maliki, a spokesman said Monday.
An Iraqi woman stands Monday in front of a Sadr City house that was destroyed during fighting.
Nassar al-Rubaie said the rival parties that dominate Iraq's government failed to meet conditions al-Sadr laid down in his March 30 declaration that temporarily halted fighting between Shiite militias and government forces in the southern city of Basra.
He said responses from members of the United Iraqi Alliance who have served as mediators in the confrontation have not met "the level of seriousness required by the Sadrists."
"We reviewed reactions to Sayyed Muqtada al-Sadr's latest statement, and we are ready for all options," said al-Rubaie, one of the 30 Sadrist lawmakers in Iraq's 275-member parliament.
Al-Sadr ordered his fighters in Basra to stand down and cooperate with government forces in the March 30 declaration, but called on the government to free non-convicted prisoners from his movement, stop what he called "illegal" raids on his followers and launch new public works projects across the country.
The warning comes amid renewed clashes between government troops and police and al-Sadr's followers south of Baghdad. Saturday, al-Sadr issued what he called a last warning to the government and told his followers to fight the "occupier" in his Baghdad stronghold of Sadr City.
Al-Maliki's government has called on the cleric to disband his militia, the Mehdi Army, or see his supporters barred from public office. Government spokesman Ali al-Dabbagh warned Sunday that "Iraq cannot be the new Somalia," with armed groups overshadowing its politics.
But al-Sadr's followers say the government's U.S.-backed crackdown on militia fighters in Basra and Baghdad is an effort to weaken the cleric's movement ahead of provincial elections scheduled for August. Sadrist lawmaker Fawzi Tarzi said Sunday that calls to disband the Mehdi Army "will mean the end of al-Maliki's government."
During a visit to Baghdad on Sunday, U.S. Secretary of State Condoleezza Rice ridiculed al-Sadr's warning of renewed warfare, accusing the cleric of hiding in Iran while his supporters fight in the streets.
"I guess it's all-out war for anybody but him," Rice told reporters at the U.S. Embassy. "I guess that's the message. His followers can go to their deaths, and he'll sit in Iran."
Al-Rubaie responded Monday that al-Sadr is "a true leader," regardless of where he is.
"Whether he is here or not, he is a true leader and is aware of everything that happens," he said.
The government crackdown in Basra resumed over the weekend, backed by U.S. airstrikes and British artillery.
U.S. troops continued their push to stop rocket attacks launched from Sadr City on Monday, using unmanned aerial drones to find and destroy five "Iranian-supported Special Group criminals," the U.S. military said.
Meanwhile, six Iraqi police officers and three Mehdi Army fighters were killed in a firefight south of Baghdad, according to an Iraqi Interior Ministry official. Three bombs targeting prime ministry workers wounded at least four people Monday morning in Baghdad, the official said, and six civilians, including a local journalist, were wounded in a drive-by shooting in the eastern New Baghdad district.
Iraqi security forces fought with Mehdi militiamen south of Baghdad Monday morning, resulting in the deaths of three Iraqi police officers and three Shiite militiamen, according to an Iraqi interior ministry official.
Three bombs targeting prime ministry workers wounded at least four people in Baghdad, the interior ministry official said.
Separately, six civilians, including a local journalist, were wounded in a drive-by shooting in the eastern New Baghdad district, an Interior Ministry official said. E-mail to a friend
CNN's Jomana Karadsheh contributed to this report.