The Court of Appeal has thrown out an appeal by Michael Adebowale to have his minimum 45 year sentence reduced.
It comes after judges rejected an appeal by his co-defendant Michael Adebolajo against his conviction.
Lee Rigby's wife sobbed with relief in court as the decision was announced.
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"My sincerest apologies to everyone who purchased tickets and were planning to come to the upcoming shows."
His comments at the Defence and Security Forum on Monday came after a £20 billion black hole in the budget for the next decade emerged.
The Foreign Secretary said he thinks the health service should be "at the very top of the list" for a windfall after the UK leaves the EU.