US Secretary of State Condoleezza Rice made an unscheduled visit to Iraq this morning, hours after US Defence Secretary Donald Rumsfeld went to Baghdad in a show of support for Iraq's new leadership.
Rice arrived on a military plane from Turkey, breaking off from a tour of several European countries.
"The turning point is that Iraq now has its first permanent government of national unity and it gives Iraq a very real chance to deal with the obviously very vexing problems it has faced," Ms Rice told reporters on board her plane, which arrived in Baghdad around midday.
Washington has pressed Iraqi leaders in the four months since an election to overcome sectarian and ethnic divisions in order to avert civil war.
Ms Rice said that the joint visit with Mr Rumsfeld was aimed at building on the political movement achieved by the formation of a national government under new Prime Minister-designate Jawad al-Maliki.
She said that a key focus of meetings she was due to have with US and Iraqi officials would be to ensure sectarianism did not influence the choice of leaders in Iraq's interior and other ministries.
Ms Rice was in Baghdad just three weeks ago, with her British counterpart, on a mission seen as a bid to break Iraq's political deadlock.
Earlier Mr Rumsfeld arrived aboard a military cargo plane for his first visit to Iraq in 2006.
"The reason we're going into Iraq is because this is a very significant time and ... the president (George W. Bush) asked us to go in to show support for this new government," Pentagon press secretary Eric Ruff told reporters travelling with Mr Rumsfeld.
Mr Rumsfeld, who last visited Iraq in December, was due to meet top Iraqi officials as well as US Army General George Casey, the top American commander in Iraq, and other military officers.
His trip comes as US military commanders contemplate reducing the number of American troops in the country in the coming months. There are about 132,000 American troops in Iraq at present.
Mr Rumsfeld has weathered criticism from six retired generals who have demanded his dismissal, accusing him of disregarding military advice, ruling by intimidation and making strategic blunders.
The visits comes on the morning after the al-Qaeda leader in Iraq, Musab al-Zarqawi, made his first ever video appearance denouncing the new Iraqi government, saying it was set up to help Washington find a way out of its predicament in Iraq.
Al-Zarqawi, who has earlier issued his messages via audio recordings, was also shown training with a group of masked men outdoors.