In an angry statement, the Belarusian foreign ministry said it told the event's organisers it would be represented by Foreign Minister Maxim Ryzhenkov at the meeting and had applied for the visas in advance.

"However, despite completing all the required procedures on our part, visas were not issued to our delegation," the ministry said.

"This situation naturally raises the question: what kind of peace and what kind of consistency can we be talking about if even the basic formalities for our participation were not fulfilled by the organisers?"

The eastern European country, ruled for more than 30 years by President Alexander Lukashenko, a close ally of Russia's Vladimir Putin, was one of only around two dozen that accepted invitations to join Trump's board.

Few Western democracies that traditionally ally with the United States have joined.

Trump established the board last year to oversee a ceasefire his administration brokered to halt two years of devastating war in Gaza.

He has since suggested expanding its remit to solving conflicts worldwide, raising concerns it could undermine the United Nations' traditional role.

Trump will wield veto power over the board and can remain its head even after leaving office.