Well this is interesting

From Le Monde:

French secret services produced nine reports between September 2000 and August 2001 looking at the Al-Qaida threat to the United States, and knew it planned to hijack an aircraft, the French daily Le Monde said on Monday.

The newspaper said it had obtained 328 pages of classified documents that showed foreign agents had infiltrated Osama bin Laden's network and were carefully tracking its moves. One document prepared in January 2001 was entitled "Plan to hijack an aircraft by Islamic radicals", and said the operation had been discussed in Kabul at the start of 2000 by Al-Qaida, Taliban and Chechen militants. The hijack was meant to happen between March and September 2000 but the planners put it back "because of differences of opinion, particularly over the date, objective and participants," Le Monde said, citing the report.

The attacks on U.S. cities that eventually took place on Sept. 11, 2001 killed almost 3,000 people.

I guess this is another reason to reject something from French Intelligence, which frankly has a much, much better record of accuracy than the CIA.