It's finally official

US President George W. Bush said the September 11 revolt of passengers against their hijackers on board Flight 93 had struck the first blow of "World War III."

In 2002, then-White House spokesman Ari Fleischer explicitly declined to call the hunt for Osama bin Laden's Al-Qaeda group and its followers "World War III."

In an interview with the financial news network CNBC, Bush said he had yet to see the recently released film of the uprising, a dramatic portrayal of events on the United Airlines plane before it crashed in a Pennsylvania field.

But he said he agreed with the description of David Beamer, whose son Todd died in the crash, who in a Wall Street Journal commentary last month called it "our first successful counter-attack in our homeland in this new global war -- World War III".

Bush said: "I believe that. I believe that it was the first counter-attack to World War III.

"It was, it was unbelievably heroic of those folks on the airplane to recognize the danger and save lives," he said.

Flight 93 crashed on the morning of September 11, 2001, killing the 33 passengers, seven crew members and four hijackers, after passengers stormed the cockpit and battled the hijackers for control of the aircraft.

The president has repeatedly praised the heroism of the passengers in fighting back and so launching the first blow of what he usually calls the "war on terror".