US President Donald Trump has announced he fired his hawkish National Security Adviser John Bolton, saying he disagreed “strongly” with him.

“I asked John for his resignation, which was given to me this morning,” Mr Trump tweeted, adding he will appoint a replacement next week.

But Mr Bolton insisted he had quit, and vowed to have his say “in due course”.

He had disagreed with the president on a number of foreign policy challenges from Afghanistan to Iran.

Mr Bolton, who had served since April 2018, was Mr Trump’s third national security adviser after Michael Flynn and HR McMaster.