The office of the ANC Chief Whip said it was saddened on Tuesday at the death of Democratic Alliance MP Cobus Schmidt.

Schmidt died in an accident in Welkom on Monday night.

"He was undoubtedly one of the hardest working MPs in that portfolio committee and always contributed excellent arguments that enhanced the quality of Parliament's oversight role," the ANC said in a statement.

"While we at times fiercely disagreed with some of his views and those of his party on a number of issues, we appreciated the fearless and forthright manner with which he raised those issues.

"We extend our heartfelt condolences to his family, his political home, the DA, his friends and colleagues."

Earlier, DA leader Helen Zille expressed shock at the sudden death of Schmidt. She described Monday night's accident as tragic.

"Cobus made a big impact in the short time he served as a Member of Parliament," she said in a statement.

Schmidt was the party's shadow deputy minister of energy. Zille said he exposed Eskom's failure to fill critical vacancies, which led to load-shedding.

He was a member of the energy portfolio committee and a constituency MP in the southern Free State. Zille described Schmidt as a patriot, who was devoted to his country and serving the public.

Prior to his election as an DA MP, Schmidt was a councillor in the Masilonyana municipality and deputy headmaster of the Reseanohetse Primary School.