US Secretary of State Condoleezza Rice has flown into Baghdad to strengthen the Iraqi government's efforts to isolate Shi'ite cleric Moqtada Al-Sadr.
Sadr has threatened an 'open war' on security forces.
The US military has killed 20 militiamen overnight in clashes in the cleric's Baghdad stronghold of Sadr City in one of the bloodiest periods in the capital in recent weeks.
"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 an uprising against the US backed government if it did not halt attacks on his followers.
The populist anti-American cleric launched two uprisings in 2004.
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 US 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.
