Bush, who earlier chaired talks in Washington on future policy in Iraq, had been expected to hold a video conference with Maliki, the BBC said.
His visit to Iraq comes less than a week after a US air strike killed Abu Musab al-Zarqawi, the leader of the al Qaeda in Iraq.
His successor, Abu Hamza al-Muhajir, has pledged to step up the suicide bombings and beheadings aimed at dislodging the 'occupying forces.' At least 16 people were killed in six separate incidents across the country Tuesday.
