US President George W. Bush smiles as he arrives with First Lady Laura Bush, for tea with Britain's Queen Elizabeth at Windsor Castle, southern England June 15, 2008. (Xinhua/Reuters Photo)

US President George W. Bush arrived in London on Sunday afternoon for a two-day visit as his final tour of Europe before leaving office.

Arriving at Heathrow, Bush and his wife, Laura, then flew by helicopter to Windsor Castle for a 45-minute tea meeting with the Queen.

US President George W. Bush walks with Britain's Queen Elizabeth in the St George's Hall, Windsor Castle, southern England June 15, 2008.(Xinhua/Reuters Photo)

They are due to have an informal dinner with Prime Minister Gordon Brown and his wife, Sarah, at Downing Street. The two leaders will discuss the allied strategy in Iraq.

In advance of his arrival, Bush told the Observer newspaper that the United States and Britain want to withdraw troops from Iraq but this should be "based on success" and not a "definitive timetable".

His comments follow reports that a final pullout of British remaining 4,500 troops could be signaled by the end of the year.

Bush said he is confident that, like him, Brown will listen to the commanders "to make sure that the sacrifices that have gone forward won't be unraveled by drawdowns that may not be warranted."

(Xinhua News Agency June 16, 2008)