President Jacob Zuma on Thursday told MPs that he does not have to provide reasons for a Cabinet reshuffle and those looking for reasons were looking "for a needle in a prairie".

Answering questions in the National Council of Provinces, one of the houses of the South African Parliament, Zuma said none of his 11 Cabinet reshuffles to date have defied logic.

"There are no decisions that have defied logic - nothing of that nature... throughout the world, generally reasons why heads of state change ministers it is their decisions, [it's] very rare that they will say what are the reasons and how do you say their decisions defy logic. It's not true," the president responded when he was pushed to provide reasons for his reshuffling of ministers, including replacing the respected Pravin Gordhan with Malusi Gigaba as finance minister and replacing Blade Nzimande with Hlengiwe Mkhize in the higher education portfolio.

"It is not only because ministers are lazy. There are other reasons that lead to presidents taking decisions, therefore to try and find the reasons is really looking for a needle in a prairie."

Opposition MPs called Zuma's decisions to shake up his cabinet irrational, with opposition Democratic Alliance MP Leon Magwebu saying the president was serving his own interests of "corruption, maladministration, and abuse of power".

Zuma's response was that Magwebu was peddling propaganda.

"His assumptions are his assumptions, not necessarily correct assumptions."

Zuma's reshuffles have angered his ruling African National Congress alliance partners, most notably the South African Communist Party (SACP) of which Nzimande is the general secretary.

The SACP and the third member of the tripartite alliance, the Congress of South African Trade Unions have called for Zuma to step down. The SACP has also threatened to go it alone in the 2019 elections.

The ANC elective conference in December will see Zuma replaced as party president, but not State president. This could only be done if the party recalled him.