Baghdad ? U.S. Secretary of State Hillary Rodham Clinton tried to reassure nervous Iraqis that the U.S. won’t abandon them, even as she said the American troop withdrawal would stay on schedule despite a recent surge in violence.

On her first visit to Baghdad as chief U.S. diplomat, Clinton said Saturday that Washington remains committed to moving U.S. soldiers out of urban areas by June 30 and pulling out combat troops from the country by 2011.

“Our strategy in working with you may be in a new phase, but we pledge our full and continuing commitment to Iraq and the Iraqi people,” she told a news conference after meeting Iraqi Foreign Minister Hoshyar Zebari.

“As we draw down militarily we will deepen our civilian cooperation,” Clinton said, standing beside Zebari in an auditorium at the Foreign Ministry.

The withdrawal will proceed in a “responsible and careful way,” she said, and would not affect efforts to improve Iraq’s security forces, or complete reconstruction and development projects.

Zebari welcomed Clinton’s “very assuring message that the United States would continue to support the efforts of the Iraqi government and the enhancement of Iraqi security and stability.” He said Iraqi authorities wanted to ensure there is “no vacuum” when U.S. troops leave.

Clinton made clear, however, that Iraqis and their security forces in particular need to overcome sectarian and other differences if they are to build a united, secure nation, she said.

Suicide bombings Thursday and Friday that primarily targeted Shiite worshippers killed more than 150 people, many of them Iranian pilgrims. The second attack, at a revered Baghdad tomb, was the single deadliest bombing in the country this year.

“I condemn these violent recent efforts to disrupt the progress that Iraq is making,” Clinton said, claiming the attacks were a sign that extremists are afraid Iraq’s government is succeeding.

But she said the response by the government and its people was “firm and united in rejecting that violence and refusing to allow it to set Iraqi against Iraqi, which is obviously one of its intended goals.” These attacks, she said, “do not reflect any diversion from the security progress that has been made.”

Iran’s supreme leader blamed the U.S. and Israel for the attacks. “Dirty hands and evil brains that founded this blind and uncontrolled terrorism in Iraq should know that the fire will burn themselves,” Iran’s state TV quoted Ayatollah Ali Khamenei as saying on Saturday.

Clinton said it was “disappointing for anyone to make such a claim since it is clearly traced to the al-Qaida remnants and other violent groups who wish to disrupt the progress of Iraq.”

Violence is at its lowest since the months after the U.S.-led invasion in March 2003. But the recent attacks have exposed gaps in security as Iraq takes over from U.S. forces in protecting the country.