US President Donald Trump has stood by his unsubstantiated claim that Barack Obama wiretapped Trump Tower last year.

He told Fox News a "wiretap covers a lot of different things" and hinted more could emerge in the coming weeks.

Mr Obama has denied the charge and former spy chiefs and several lawmakers have said they have seen no evidence.

But in the interview, Mr Trump said: "I think you're going to find some very interesting items coming to the forefront over the next two weeks."

The president's first comments about the wiretap accusation he made two weeks ago will be broadcast in full on Wednesday night.

Earlier this month, Mr Trump tweeted that President Obama had wiretapped his phones during the presidential campaign.

In a series of tweets, he accused his predecessor directly, asking: "Is it legal for a sitting President to be 'wire tapping' a race for president?"

Despite repeated requests, the White House has not provided any evidence to support this claim.

But Mr Trump asked Congress to examine the allegation as part of an investigation into alleged Russian meddling in last year's election