Gordon Brown’s office declares that the UK notified the US over a year ago about Umar Farouk Abdulmutallab’s links to terrorism:

MI5 told US about Detroit bomber’s terror links ‘a year ago’
Britain told American intelligence agents more than a year ago that the Detroit bomber had links to extremists, according to Downing Street.

The prime minister’s spokesman indicated that Umar Farouk Abdulmutallab was named in a file of people based in Britain who had made contact with radical Muslim preachers. The file was said to have been sent to the US authorities in 2008.

But,

There is no suggestion that the US did not act on intelligence information that they received from the UK.”

Meanwhile at the US,

White House sources disputed the Downing Street account, stating that no such intelligence information was passed by Britain before the attempted Christmas Day attacks. The White House declined to respond officially.

Amazing that the Obama administration didn’t say that it’s all Bush’s fault since he was president then. But hey, President Obama briefed on Christmas terror threats days before Abdulmutallab incident

President Obama was briefed on potential holiday threats just three days before a Nigerian with Al Qaeda ties tried to bring down an airliner on Christmas Day, according to a report.
…
Attorney General Eric Holder, Homeland Security Secretary Janet Napolitano and FBI Director Robert Mueller were at the briefing.

Administrative officials admitted after the attempted attack that they had “bits and pieces” of information that if knitted together could have foiled the Christmas Day plot.

“Never mind!”