Trump Could Sabotage Brexit Trade Deal If He Doesn't Get Invited to Prince Harry's Wedding

President Donald Trump might jeopardize a post-Brexit trade deal with the U.S. if he is not invited to Prince Harry's wedding, the author of a controversial book on the magnate-turned-president has claimed.

The prince and his fiancée, Meghan Markle, are due to tie the knot this May. So far, it seems unlikely that Trump will be invited to the event.

However, Michael Wolff, journalist and author of Fire and Fury: Inside the Trump White House, warned that Trump "doesn't like being snubbed."

"[He] wants to be the center of attention all the time," he told the Mail on Sunday.

"Trump's foreign policy doctrine is simple: you Brits suck up to him and enlist in whatever geopolitical fantasy he has going, he'll give you what you want—though only if it doesn't hurt him. It is not so much vengeance, rather 'you flatter me and I'll flatter you.'"

The U.S. is the biggest export market for the U.K. after the European Union.

Matthew Goodwin, Professor of Politics at Rutherford College, University of Kent, believes that the trade deal could be at stake due to Trump's unpredictability.

"Barack Obama famously said that Britain would be at the back of the queue when it came to trade talks. Since the vote for Brexit many Brexiteers have assumed that Donald Trump will instead put Britain at the front of the queue," he told Newsweek.

"However, what they may have overlooked is just how unpredictable and shallow the new President really is," he said.

 Theresa May and   Donald Trump
British Prime Minister Theresa May and U.S. President Donald Trump wait for a meeting at the Palace Hotel in New York, on the sidelines of the 72nd United Nations General Assembly, on September 20, 2017. Trump might jeopardize a post-Brexit trade deal with the U.S. if he is not invited to Prince Harry's wedding, the author of a book has claimed. BRENDAN SMIALOWSKI/AFP/Getty Images

Wolff, whose book claimed Trump might suffer from dementia, added that the 71-year-old leader had no idea of what Brexit was until a few weeks before the 2016 referendum.

"He sees the queen in reality TV show terms. That's the Trump modus operandi," he added. "He will try to Trumpalize the queen and Buckingham Palace."

While Prime Minister Theresa May confirmed that Trump is due to visit the U.K., tensions between the two countries have grown in recent months, after May criticized Trump for sharing videos from far-right group Britain First on Twitter.

During an interview on the BBC's Andrew Marr show, May was also asked what she thought of Trump's mental health. She replied: "[He is] taking decisions on what he believes is in the best interest of the United States."

The claims in Wolff's book have sparked outrage. Both Trump and the White House denied the allegations contained in Wolff's work and condemn it. The president called the author a "fraud" and said his book was a "disgrace".

He also denied allegations he suffers from mental problems and called himself a "very stable genius".