Mazibuko, 34, a rising star in the party, said in South Africa’s Sunday Times that she would leave to study at Harvard University in the United States for a year.

“I took the decision in September when, during a visit to Yale University with others pursuing high-profile careers, the value of such a break became clear to me,” she was quoted as saying.

“I had considered it before, and I believe the decision is the right thing at the right time for the DA and for me because it will improve what I can offer the DA politically.”

Mazibuko was number three on the party’s national election list, and set to head the party’s enlarged 89 seats in parliament after winning 22.23 percent in last Wednesday’s poll.

The ruling African National Congress took 62.15 percent in the vote.

She denied that a spat with party leader Helen Zille last year over opposing views on the DA caucus influenced her decision.

Well-spoken Mazibuko became a member of parliament after the previous polls in 2009 and caucus leader two years later, gaining respect for well thought-through answers and impressive performances in debates.

But detractors criticised her as a figurehead handpicked by Zille in an effort to shake off the DA’s image as a party for whites in a country where race-based politics still is very important.

Neither Mazibuko nor party spokespeople were immediately reachable for comment.