Billionaire businessman Sir Richard Branson has launched a scathing attack on United States President Donald Trump, saying he's been "an embarrassment to the world" since taking office.

Sir Richard was in New Zealand for a talk at Auckland's Vector Arena on Sunday, where he was interviewed by former Prime Minister John Key.

It was a night for the high-flyers; the cheapest seats were almost $700, with tables of 10 costing between $7000 and $11,500.

In an exclusive interview with Newshub, the Virgin co-founder lamented Mr Trump's first "disastrous" days in office.

"I've found it rather an embarrassment to the world to have an individual running America who... does not speak the truth all the time, who tries to, instead of opening borders to immigrants, has made it really difficult to get in, and the list goes on and on and on.

"I think Trump is the one businessperson I know who is certainly not the right person to be running a great country like America," he says.

However, Sir Richard did see a silver lining in the troubled presidency.

"The first days in office have been so disastrous I think the chances of it lasting more than one term are extremely unlikely and I think that's the only saving grace about the way he's behaving at the moment."

It isn't the first time the Virgin group co-founder has been scathing of Mr Trump.

In October, Sir Richard documented his first encounter with him several years earlier, before he arrived on the political scene.

He'd been invited to lunch at Mr Trump's Manhattan apartment where all he talked about were the five people he'd "spend the rest of his life destroying" after they refused to help him with his latest bankruptcy.

"He didn't speak about anything else and I found it very bizarre. I told him I didn't think it was the best way of spending his life. I said it was going to eat him up, and do more damage to him than them," Sir Richard wrote in a blog post.

He wondered if he was asked to lunch to give Mr Trump financial help - he said he'd also turn him down if that was the case.

Sir Richard said he left the lunch feeling "disturbed and saddened" having been given a glimpse of Mr Trump's "vindictive streak".

"For somebody who is running to be the leader of the free world to be so wrapped up in himself, rather than concerned with global issues, is very worrying."

Sir Richard isn't the only one with a disparaging view of the 45th President, with the latest polls showing just a 37 percent approval rating for Mr Trump.

Sir Richard also recently played host to Mr Trump's predecessor, Barack Obama, and former First Lady Michelle on Necker Island in the British Virgin Islands.

He wouldn't be drawn on any comments the former president had on his successor, saying the Obamas were there purely to relax.

"I think it would be unfair for me to comment on conversations with the Obamas, but it was an honour and a delight having them stay with us. I had great fun taking on the President and seeing whether I could foil board before he learned to kite, and I lost.

"To be perfectly honest, the Obamas wanted to relax, they had just been in office for eight years, they came to our island to completely switch off and relax and the last thing I think they wanted to do was worry about Trump."

During the Obamas' break, they were both pictured grinning ear-to-ear and having a great time kitesurfing.

"He was free, from hard, hard work for eight years and he was enjoying himself and so he should."

Newshub.

