The Nigerian man known as “the underwear bomber” was ordered to change out of an oversized white T-shirt yesterday at the start of his trial on charges of trying to blow up a US-bound airliner.

Umar Farouk Abdulmutallab, who has insisted on representing himself, ran into his first setback as jury selection got underway when Judge Nancy Edmunds called a short break and told the 24-year-old Nigerian to change into a shirt and tie.

Judge Edmunds has repeatedly urged Mr Abdulmutallab to let a lawyer argue his case, and appointed “standby counsel” to help him contest charges that he tried to kill nearly 300 people aboard a Northwest Airlines flight from Amsterdam to Detroit.

While he accepted some help, Mr Abdulmutallab insists he will make his own opening statement and will question witnesses during what is expected to be a weeks-long trial.

The trial will be closely watched as it comes after the killing of Al-Qaeda preacher Anwar al-Awlaqi in a US air strike in Yemen. US intelligence officials have repeatedly linked the US-born cleric to the Christmas Day plot.

The Christmas Day plot was foiled when explosives stitched into Mr Abdulmutallab’s underwear failed to detonate and only caused a small fire, allowing passengers and crew members to restrain him.

The botched operation triggered global alarm and led the United States to adopt stringent new screening and security measures, including controversial pat-downs at airports and a massive expansion of the no-fly list.

The reputation of the nation’s intelligence services also took a hit because Mr Abdulmutallab’s father, a prominent Nigerian banker, had warned the CIA about his son’s growing Islamic radicalisation.