BBC News with Marion Marshall

The man accused of trying to blow up an airliner over the American city of Detroit on Christmas Day in 2009 has dramatically changed all his pleas to guilty. Nigerian-born Umar Farouk Abdulmutallab is facing charges of trying to kill the 300 people on board the Northwest Airlines flight from Amsterdam. Jonny Dymond reports.

After a 45-minute recess at the start of proceedings, US District Judge Nancy Edmunds asked Umar Farouk Abdulmutallab if he wanted to plead guilty and waive his right to a trial. "That's right," he replied. Then each charge was read out to him.

Standing in front of the judge, flanked by the defence and prosecution lawyers, he replied to each one "I plead guilty." In a statement to the court, Abdulmutallab said his attempted bombing of Northwest Airlines Flight 253 was a religious obligation driven by what he called US attacks upon Muslims.

The American Secretary of State Hillary Clinton has described an alleged Iranian plot to kill the Saudi ambassador to the US as a dangerous escalation of Iran's sponsorship of terrorism. Speaking earlier at a conference in London, Prince Turki al-Faisal, the former Saudi ambassador to the US, said the plot was criminal.