South Africa's firebrand opposition politician Julius Malema and his wife Mantoa Matlala have threatened to sue a governing party MP for defamation if he fails to retract allegations that Mr Malema abused his wife.

African National Congress (ANC) MP Boy Mamabolo responded to the threat by tweeting: "Bring it on let’s meet in court."

But he came under fire from the ANC Women's League, which accused him of launching a "misguided attack" on an "innocent woman who is not even a politician".

Lawyers for the couple said that if Mr Mamabolo refused to apologise, Mr Malema and Ms Matlala would sue him for one million rand ($66,000; £51,000) each.

Mr Mamabolo made the allegation during a week of intense political acrimony between Mr Malema's Economic Freedom Fighters (EFF) and the ANC.

It also saw Mr Malema accuse President Cyril Ramaphosa in the parliament of abusing his late wife, Nomazizi Mtshotshisa. Mr Ramaphosa did not respond to the allegation.

The speaker, however, demanded that Mr Malema withdraw the remark. He refused and was ordered to leave the chamber.

The EFF tweeted a letter sent to Mr Mamabolo by Ms Matlala's lawyers that said: "Your false accusations have now cast a dark cloud over the entire family."

Mr Malema said he had "never laid a hand on any woman, my wife in particular, including all children".

Mr Malema married Ms Matlala at a lavish ceremony in 2014.