Meanwhile, Botswana has summoned United States ambassador to express displeasure at the "highly irresponsible, reprehensible and racist" comments by Trump.
Trump's alleged statement also prompted outrage from the African Union (AU), the organization that includes all the 54 African UN states plus Western Sahara, which is not recognized by the UN.
The president's latest comments drew reactions from overseas on Friday.
"Haitians don't deserve such treatment", said Paul Altidor, the Haitian ambassador.
Mr. Mahama condemned the reported comments and urged the African Union to take action following these developments.
Trump wants to change the rules for entering the United States, and stepped into controversy when he said the nation should be seeking immigrants from countries such as Norway instead of countries such as Haiti.
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Prominent Kenyan commentator Patrick Gathara, said that Trump's words were nothing new from a "racist and ignorant" administration, nor from the West at large.
"Trump denied saying anything derogatory about Haitians". I could write about the beauty of the island, the music and vibrant art, the majesty of the mountains, the crystalline blue of the water surrounding her, the resilience of the Haitian people, our incredible work ethic, our faith.
"In later tweets, the president described his language as "tough" but denied using the term "****hole".
The president's remarks angered several countries, prompting them to issue strongly-worded statements condemning his comment.
Haiti, though the poorest country in the Americas, has played an outsized role in the history of the region. "The contribution and spirit of these immigrants, as American citizens and as citizens who honor their homeland, may well be the greatest symbol of what makes America great - or at least of what can". Haitians gave their blood back in 1779 to fight for the independence of this country.
Loans from French banks to cover indemnity payments to Paris for independence were only paid off in 1947.
Haiti also supported the American Revolution by sending troops to the Battle of Savannah in Georgia in 1779. The embassy in South Africa said the United States "deeply respects" the people of Africa, and "there has been no change in our dedication to partners & friends across the continent". "We even made the ultimate sacrifice when we shed our blood in Savannah", the ambassador said. The Trump administration is ending those protections for people from Haiti, El Salvador and Nicaragua, and suggested it will do the same for Hondurans.