Donald Trump: Barack Obama is the founder of so-called Islamic State

Donald Trump has accused US President Barack Obama of founding so-called Islamic State.

Speaking at a rally outside Fort Lauderdale, Florida, the Republican presidential candidate repeated the allegation three more times for emphasis.

Mr Trump had previously accused Hillary Clinton of founding the militant group, but in Florida he shifted the blame to President Obama, instead arguing that "crooked Hillary Clinton" was actually the group's co-founder.

The billionaire has long blamed President Obama and former secretary of state Mrs Clinton for pursuing policies in the Middle East that created a power vacuum in Iraq that was exploited by so-called Islamic State.

Mr Trump has sharply criticised the President Obama for announcing he would pull US troops out of Iraq, a decision that many of the president's critics say created the kind of instability in which extremist groups like so-called Islamic State thrive.

Mr Trump's accusations and his use of the president's middle name, Hussein, echoed previous instances where he has questioned President Obama's loyalties.

The White House declined to comment on Mr Trump's accusations.