US Secretary of State Condoleezza Rice has given her support to the Iraqi government's efforts to isolate Shi'ite cleric Moqtada al-Sadr, who has threatened an "open war" on security forces.
Arriving on an unannounced visit to Baghdad, Rice said she wanted to support what she called a new political "centre" in Iraq that has backed Shi'ite Prime Minister Nuri al-Maliki's crackdown on Sadr's Mehdi Army militia.
"It is indeed a moment of opportunity in Iraq thanks to the courageous decisions taken by the prime minister and a unified Iraqi leadership," Rice said in brief televised remarks with President Jalal Talabani after they held talks. "And of course the Iraqi security forces have fought very bravely in this recent operation."
Rice, who also met Maliki, arrived a day after Sadr threatened uprising against the US-backed government if it did not halt attacks on his followers.
The Iraqi Shi'ite cleric threatened "open war" with the government unless it chose what he called the "path of peace". The statement ratchets up the tension between the cleric and Prime Minister Nuri al-Maliki. Maliki has launched a crackdown on Sadr's Mehdi Army militia and threatened to bar his mass movement from political life.
"I'm giving the last warning and the last word to the Iraqi government - either it comes to its senses and takes the path of peace ... or it will be the same as the previous government," Sadr said, referring to Saddam Hussein's fallen regime but without elaborating.
The cleric added: "If they don't come to their senses and curb the infiltrated militias, then we will declare an open war until liberation."
A rebellion by the Mehdi Army militia - which has tens of thousands of fighters - could abruptly end a period of lower violence at a time when U.S. forces are starting to leave Iraq.
Rice did not take questions during the televised appearance and has so far not commented directly on Sadr's threat.
Maliki launched a crackdown on Sadr's followers late last month that has led to the worst fighting in Iraq in nearly a year. The crackdown has been backed by all parties across Iraq's sectarian and ethnic divide except the Sadrist movement.
Referring to that support for Maliki, Rice earlier told reporters there was a "coalescing of a centre in Iraqi politics" that was working together better than at any time.
"I would like just to see what we can do to promote that kind of centre that I think is clearly coming together," she said.