British billionaire Richard Branson says that his first encounter with Donald Trump was a memorable one -- and not in a good way.

In a blog post on Virgin's website, Branson recalls being invited by Trump to have lunch with him at his Manhattan apartment, where he mostly skipped over pleasantries and instead launched into a tirade about a topic near and dear to his heart: Exacting revenge on his foes.

"Even before the starters arrived he began telling me about how he had asked a number of people for help after his latest bankruptcy and how five of them were unwilling to help," Branson writes. "He told me he was going to spend the rest of his life destroying these five people. He didn’t speak about anything else and I found it very bizarre."

Branson then says that Trump's lust for vengeance against his detractors is the single most disturbing aspect of his presidential candidacy.

"I left the lunch feeling disturbed and saddened by what I’d heard," he said. "What concerns me most, based upon my personal experiences with Donald Trump, is his vindictive streak, which could be so dangerous if he got into the White House. 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."

Read the whole post at this link.