Al-Qaeda's second-in-command, Ayman al-Zawahiri, has mocked a US congressional bill that sets out at timetable for US troops to leave Iraq.
Al-Zawahri is second in line to al-Qaeda leader Osama Bin Laden
He called the bill evidence of US failure and frustration and said it would "deprive us of the opportunity to destroy the American forces".
Egyptian-born Zawahiri made the comments in a 67-minute-long video message posted on Islamist websites.
US President George W Bush vetoed the congressional bill on Thursday.
"We ask Allah that they only get out after losing 200,000 to 300,000 killed, so that we give the blood spillers in Washington and Europe an unforgettable lesson," Zawahiri said in the video message.
He also scorned the US-led security surge in Iraq, urging Mr Bush to meet him in a cafeteria in the Iraqi parliament where a legislator died in a suicide bomb attack last month.
It is the fifth apparent audio or video message from Osama Bin Laden's number two this year.