US Secretary of State Condoleezza Rice praised the Iraqi government Sunday for government-led assaults on radical militias, as the top US diplomat made a surprise visit to Baghdad in a show of support for the country's leaders. Rice's brief heavily guarded stop was not announced in advance, in keeping with security precautions adopted by all top US officials who remain targets of the anti-American insurgents five years after the US-led invasion of Iraq and the fall of Saddam Hussein. Rice met with Iraqi Prime Minister Nouri al-Maliki, his Kurdish president and other top officials. She was also honoring Americans killed in the Green Zone, the heavily protected compound that houses the US embassy and much of the Iraqi central government. During his meeting with Rice, al-Maliki said the assaults in Basra represent a strong blow to all lawbreakers, showing the determination to confront the militias, according to a press release by the prime minister's office. Iraqi President Jalal Talibani told Rice, "We are living in the Iraqi political spring." Rice said it is "indeed a moment of opportunity, thanks to the courageous decision taken by the prime minister and a unified Iraqi leadership." In the northern part of Iraq, US and Iraqi troops have stepped up security operations in Mosul, believed to be one of the last urban strongholds of al-Qaida in Iraq. Al-Maliki told Rice that government forces are preparing to finish the battle against militants in Mosul in the coming days, according to the press release by the prime minister's office. Rice told reporters she sees signs that al-Maliki's assaults on militia forces last month have brought sectarian and ethnic groups together in an unprecedented way. She said she wants to capitalize on that cohesion. Rice traveled to Iraq, she said, to promote new Sunni and Kurd support for the US backed Shiite government. Rice had a brief exchange with al-Maliki in which they both noted improvements in security. They then went into a private meeting along with the top US ground commander, Gen. David Petraeus, and US Ambassador Ryan Crocker. US officials usually travel from the airport by helicopter because it's safer, but on Sunday Rice went to the Green Zone by motorcade because of a sand and dust storm. En route to Iraq, Rice told reporters traveling with her that she is not trying to make a point about security gains in Iraq by visiting now. "I think everybody knows it is still a dangerous place," she said aboard her plane. Her main goal is to spotlight what she calls encouraging political signs following the Basra crackdown. Sunni and Kurdish politicians have offered public support to al-Maliki following the operation, and the Bush administration argues he could emerge stronger from what had appeared to be a military blunder. "This is, I think, an important time," Rice said. "You've seen a coalescing of a center in Iraqi politics," and she wants to promote it, Rice said. The head of the Kurdish self-ruled region, Massoud Barzani, has offered Kurdish troops to help fight anti-American cleric Muqtada al-Sadr's Mahdi Army militia. More significantly, Sunni Arab Vice President Tariq al-Hashemi signed off on a statement by Talabani, a Kurd, and the Shiite vice president, Adil Abdul-Mahdi, expressing support for the crackdown in the oil-rich southern city of Basra. Al-Hashemi is one of al-Maliki's most bitter critics and the two have been locked in an acrimonious public quarrel for a year. Al-Hashemi has accused the prime minister of sectarian favoritism and al-Maliki has complained that the Sunni vice president is blocking key legislation. Sunnis are looking for concessions from al-Maliki, whom they accuse of monopolizing power. Some leaders among both Sunnis and Shiites suspect al-Maliki's real aim in launching the Basra operation was to weaken Shiite opponents ahead of provincial elections this fall. "There are those who questioned whether or not the prime minister was prepared to go after militias that were associated one way or another with political elements in his coalition ... and there have been questions from the Arab states," Rice said. "I think he's answering that question." During five days of heavy fighting last month, Iraqi troops struggled against militiamen, particularly the Mahdi Army loyal to al-Sadr. The ill-prepared Iraqi military was plagued by desertions and poor organization and US troops had to take over in some instances. The offensive was inconclusive, with Iran helping mediate a truce. Still, the crackdown appears to have succeeded in giving some sense of central government control in Basra, Iraq's second-largest city and the emergence of a common cause could help bridge Iraq's political rifts. The Bush administration also points to the upcoming election and passage of some long-stalled legislation as signs of emerging political cohesion. "This is a complicated process, but it is a process that has begun in Iraq," Rice said. "It's not been the smoothest of processes, but it is an important step that the Iraqi government has taken." Al-Sadr gave what he called a "final warning" to the al-Maliki government Saturday to halt a US.-Iraqi crackdown against his followers or he would declare "open war until liberation." A full-blown uprising by al-Sadr, who led two rebellions against US-led forces in 2004, could lead to a dramatic increase in violence in Iraq at a time when the Sunni extremist group al-Qaida in Iraq appears poised for new attacks after suffering severe blows last year. Rice told reporters it has been difficult to determine al-Sadr's motives, adding that the fate of his political movement would be a matter for the Iraqis to decide. The US would not object, she said, if his political forces take part in upcoming elections this fall, so long as they do so responsibly. Rice left Washington on Saturday for the region. She will also meet Persian Gulf diplomats in Bahrain, and a wider group of Arab states and others in Kuwait. The Kuwait meeting is the third such regional gathering centered on ways that neighbor states can help Iraq secure its borders, improve internal stability and deal with the tide of refugees that fled sectarian violence and economic decline in Iraq. She said Iraq's Arab neighbors have few remaining excuses for withholding diplomatic and economic support for the US-backed government in Baghdad, now that daily life in Iraq is less deadly and the government has demonstrated resolve against militias.