A report that US President Donald Trump made crude, disparaging remarks about Nelson Mandela has drawn an angry response from South Africa’s ruling party.

According to a book written by Michael Cohen, President Trump’s former personal lawyer, he said that Mr Mandela, who guided South Africa in its political transition from a racist apartheid government to a democracy, was a terrible leader.

Mr Cohen wrote that after Mr Mandela’s death in 2013, President Trump said: “Mandela f***** the whole country up. Now it’s a shithole. F*** Mandela. He was no leader.”

Mr Mandela, who won the Peace Prize in 1993 along with apartheid leader Frederik Willem de Klerk, is widely revered by all racial groups in South Africa.

Internationally, he generally has a glowing reputation as a skilled statesman who avoided a nationwide bloodbath as the country abandoned apartheid.

The report about President Trump’s comments could also impact the US presidential election in November in which he is seeking a second term in office, angering not only black Americans but white voters who see Mr Mandela as a peace icon.

South Africa’s ruling African National Congress party said on Tuesday that President Trump is not fit to comment on Mr Mandela’s accomplishments.

“All freedom-loving people of the world are appalled by these insults, which come from a person who himself is not a model of competent leadership,” said the ANC statement, adding that President Trump is the most “divisive, misogynistic and disrespectful person” ever to be president of the United States.

Mr Mandela’s dedication to “peace and a just society” stands in “stark contrast” to President Trump’s policies, said the ANC.

“The mark of a true leader is not how many enemies you create but how many friendships you cultivate, even where strong differences of opinion exist,” said the ANC, adding that if Mr Mandela were alive today, he would reach out to President Trump to discuss international issues.

The Nelson Mandela Foundation also criticised President Trump for the insulting remarks about Mr Mandela attributed to him by Mr Cohen, who has been convicted of fraud and perjury.

“We do not believe that leaders who conduct themselves in the way Mr Trump does are in a position to offer authoritative commentary on the life and work of Madiba (Mandela’s clan name),” the foundation said in a statement.

The US ambassador to South Africa, Lana Marks, responded to the controversy with a diplomatically worded statement.

“I have discussed South Africa with President Trump many times, and he has only ever spoken positively about the country,” said Ms Marks.

“The US remains committed to working together with South Africa to realise the promise of a more peaceful, more productive, more prosperous 21st century Africa.”