Hillary Clinton has landed in the Iraqi capital Baghdad for her first visit to the country as US secretary of state, BBC reported.
Her visit comes after two days of suicide bomb attacks on Baghdad and other Iraqi towns which killed at least 155 people and wounded many others.
President Barack Obama, who visited Iraq a couple of weeks ago, has committed the US to withdrawing troops from Iraqi cities by the summer.
All combat brigades are to leave by next summer.
Before leaving for Baghdad, Mrs Clinton said the recent upsurge in violence was a tragic signal that Iraq was in fact on the right path.
She said the Iraqi government had made impressive progress but there were people who did not want it to succeed.
She described those behind the violence as rejectionists.
Mrs Clinton said her trip was meant to send a clear signal to the Iraqi people that the US was committed to helping them navigate the difficult transition period.
America's top diplomat will spend the day in Baghdad, holding talks with Iraqi officials, including Prime Minister Nouri Maliki and her Iraqi counterpart Hoshyar Zebari as well as the top US commander Gen Raymond Odierno.
She is also meeting a group of Iraqi widows and holding a "town-hall" meeting with Iraqis from different civil society and interest groups.