Donald Trump reportedly signed a letter advising African leaders that he "deeply respects" the people of Africa ahead of this weekend's African Union summit.
"In the coming year, I look forward to building on relationships established during the African Leaders' Lunch during the United Nations General Assembly, the Africa Ministerial in Washington".
The 55-nation African Union chaired by Kagame demanded an apology, although Trump had denied making the remark as relayed by USA lawmakers that were present at the meeting.
The president has denied that he used the derogatory language, purportedly comparing Haiti and African nations to a dirty toilet.
Many in Africa were taken aback by the comments after almost a year of little attention to Africa by the Trump administration.
Trump's letter, seen by The Associated Press and confirmed by two USA officials, says the U.S.More news: Wigan send West Ham crashing out
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He said the USA supports AU's fight against terrorism, something he said will collectively improve air transport security, foster better trade between the USA and the African continent and safeguard legal immigration.
In the letter, Trump also offered his "best wishes for a successful summit", and noted that his administration is committed to ensuring "free, fair and reciprocal trade" with African nations, while working to "safeguard legal immigration", according to NBC News.
In a letter dated January 25, Trump paid glowing tribute to the African Union as it gathered in Addis Ababa, Ethiopia, for the Peace and Security Council meeting at the 30th AU Summit.
Dozens of former USA ambassadors to African countries wrote a letter to Trump expressing "deep concern" over his comments and asking him to reconsider.
The letter does not include details about Tillerson's upcoming visit.
"Had very good bilateral meeting with @realDonaldTrump!"