US Secretary of Defense Donald Rumsfeld paid an unannounced visit to Iraq on Thursday.

Rumsfeld was greeted by Gen. George Casey, the top US commander in Iraq, at the airport, after a flight from Afghanistan.

Rumsfeld's visit came against a backdrop of mounting pressure on the Bush administration to speed up US troops' withdrawal from Iraq.

However, Rumsfeld declined to set a timetable for that, insisting that any further military cuts must depend on assessments of the security situation.

"That decision has not been announced," he told reporters.

Rumsfeld's visit came after two lightning visits by US Vice President Dick Cheney and British Prime Minister Tony Blair earlier to the violence-ravaged country.

Source: Xinhua