The Western Cape human settlements MEC said the letter was revived to tarnish his image in order to prevent him from being officially elected DA leader in the province.
His party will officially elect its leader at the end of the year.
Madikizela also linked the re-emergence of the letter to supporters of KwaZulu-Natal MPL Mbali Ntuli, who is facing charges of liking a Facebook post that accused Western Cape Premier Helen Zille of being a racist. He is the complainant in that matter.
“There are people now who want to settle scores because they believe I complained against Mbali, and now those people are making up stories which are non-existent,” he said.
Ntuli denied any knowledge of the letter.
According to a script written by DA federal chairperson Athol Trollip in 2015, Madikizela had circulated an SMS accusing Maimane of being “not black enough because he is married to a white woman”.
The letter also alleged that Madikizela had accused Maimane of surrounding himself with white people.
It is further alleged he (Madikizela) made the remark before the DA congress which elected Maimane as leader.
Trollip’s letter quoted Madikizela saying, “Of course we can’t allow a situation where Mmusi become (sic) the only black leader we elect out of this congress. I can say that on any platform.”
Madikizela, who denied making the remarks, said people who circulated the letter had an agenda against him.
“When we are approaching congress people come with all sort of nonsensical stories.”