Donald Trump's first primetime TV interview was less than half as popular Barack Obama's

Tally comes shortly after spat with CNN over ratings

Ratings for Donald Trump's first prime-time TV interview as President were lower than Barack Obama's by nearly 10 million viewers.

About 7.5 million people watched Mr Trump's interview with ABC News' David Muir, which compared unfavourably to the 17.04 million who tuned in to see Barack Obama on CBS News', 60 Minutes in March 2009.

Mr Trump also lost out to Mr Obama in the ratings war immediately after they had won the presidency.

The former reality TV star's post-election appearance on 60 Minutes in November drew 18.77 million pairs of eyeballs. Mr Obama's corresponding interview was watched by 24 million Americans.

Mr Trump's lower ratings on Wednesday can be explained partly by the timing of the interview, according to the US entertainment magazine, Variety.

Mr Obama's slot followed highly popular coverage of college basketball's "March madness" championship, providing a strong lead-in, it said.

During his first presidential interview, Mr Trump returned to the subject of the crowd size at his inauguration ceremony.

"I had a massive amount of people here," he said, adding that the media "were showing pictures that were very unflattering, as unflattering — from certain angles — that were taken early and lots of other things."

He said: "In terms of a total audience including television and everything else that you have we had supposedly the biggest crowd in history."

The new President has repeatedly feuded with the media about perceived unflattering coverage.

In the latest spat, US broadcaster CNN replied to a tweet from Mr Trump accusing the broadcaster of being "fake news" by showing one of the president's claims to be false.

In his tweet, Mr Trump congratulated Fox News "for being number one in inauguration ratings" and said they were "many times higher" than CNN.

"Congratulations to Fox News for being number one in inauguration ratings. They were many times higher than FAKE NEWS CNN," Mr Trump wrote. "Public is smart!" he added.

However, CNN responded by sharing the viewing numbers.

It said: "According to Nielsen cumulative numbers, 34 million people watched CNN's inauguration day coverage on television. 34 million watched Fox News. There were an additional 16.9 million live video starts on CNN Digital platforms. Those are the facts."