An energy summit, scheduled to take place in Madison, Wisconsin, had to be cancelled as all the delegates, hailing from Africa, were denied visas.
Mary Flowers, one of the organisers of the summit, told Voice of America that the last three events had encountered issues but had continued as around 40 per cent of the participants had been denied visas.
"This year it was 100 per cent. Every delegation. And it was sad to see because these people were so disheartened," she said.
Samba Baldeh, an elected official in Madison who was born in Gambia, said this was the effect of the Trump administration's problematic handling of visas.
"This is part of a broad policy of the Trump administration to deny, stall and obstruct visa requests regardless of their source," he said.
Baldeh told the Wisconsin State Journal that the US had "squandered a great opportunity for energy-deprived nations to work with advanced energy providers of the US and Wisconsin".
According to Kenya's Business Daily, speakers at the event included ambassadors to the US from Botswana, Ghana and South Africa, as well as the co-ordinator of former President Barack Obama's Power Africa programme.