Baghdad- US Secretary of State Hillary Clinton has arrived in the Iraqi capital on an unannounced visit, Voices of Iraq news agency reported on Saturday. The visit comes at a time as the new US ambassador to Iraq, Christopher Hill, is taking up his office.

The trip - Clinton's first to Iraq as secretary of state - also comes after 48 hours of suicide bombings in Baghdad and other cities which have killed at least 155.

President Barack Obama vowed to withdraw US combat troops from Iraqi cities by summer during a recent visit to Iraq.

Before heading to Baghdad, Clinton said that the recent escalation in violence in Iraq is a tragic indicator that Iraq is on the right path.

Clinton is expected to meet with Iraqi Prime Minister Nuri al-Maliki, her counterpart Hoshyar Zebari, and the top US commander in Iraq General Raymond Odierno.