President George W Bush [Images] on Monday made a surprise visit to Iraq to have a first-hand assessment of the US troop 'surge' even as its ally Britain withdrew the last of its forces from Basra city in the south.

Bush secretly flew 11 hours to al-Asad air base in Anbar province, bypassing Baghdad in what is perceived as a sign of his impatience with the political paralysis in the Iraqi capital.

He was joined by his top advisers, including Secretary of State Condoleezza Rice and National Security Adviser Stephen Hadley.

The session at al-Asad will be 'the last big gathering' of President's war advisers with Iraqi leaders before he makes a decision on a way forward in Iraq, the Pentagon said.

The visit comes as a showdown nears with Congress over the US troop buildup in the war-torn country. The Bush administration maintains that the 'surge' is working and this confidence is reflected in a plan to ask Congress for an additional $30 to $50 billion for the operations in Iraq.

Image: President Bush with a US marine as he tours al-Asad Air Base in Anbar Province of Iraq.
Photograph: Getty Images | Reportage: PTI