President Cyril Ramaphosa will have a tough time choosing who his deputy in government is going to be after it emerged that Mpumalanga premier, and the ANC's second-in-command, David Mabuza has thrown his hat into the ring.

As Ramaphosa took over as the country's fifth president last week, speculation was rife that he would pick a woman as his deputy when he announces his cabinet some time before the end of next week.

Human Settlements Minister Lindiwe Sisulu and Science and Technology Minister Naledi Pandor are the two names that have been mentioned as firm favourites to take over from Ramaphosa as deputy president.

But, in a new twist to the ongoing realignment of the ANC's internal politics following the fall of former president Jacob Zuma, Mabuza has given his strongest indication yet that he wants to move to the deputy presidency immediately, and is not interested in waiting until after the 2019 elections.

Mabuza was elected ANC deputy president at the party's national conference in December.

However, it is not a given that the ruling party's deputy president becomes the country's deputy president.

In 1999, for instance, then president Thabo Mbeki offered the deputy presidency to IFP leader Mangosuthu Buthelezi ahead of his then ANC deputy, Zuma.

Mabuza's spokesman Zibonele Mncwango told Sowetan yesterday that the Mpumalanga premier was ready to ascend immediately to the deputy presidency if Ramaphosa chose him.

"It is neither a matter of personal preference, choice or ambition, but a matter of call of duty and deployment by the ruling party.

"The premier remains at the disposal of the organisation where he will suitably be deployed, as it is the prerogative of the president to appoint people in his cabinet," said Mncwango on behalf of Mabuza.

The ANC Youth League and ANC Women's League in Mpumalanga warned yesterday that failure by Ramaphosa to appoint Mabuza to the post could lead to divisions within the ANC.

ANCYL provincial secretary Pholoso Mbatsane said voters would want to know why Ramaphosa ignored his ANC deputy when choosing his deputy if someone other than Mabuza was appointed.

"People are going to ask why [the] deputy president of the ANC was not appointed deputy president of the country. It will be something foreign," said Mbatsane.

Mbatsane said Mabuza has served the province exceptionally and it was now time for him to serve the country at national level.

Women's league provincial secretary Lydia Moroane said the ANC's gender parity policy should not be used as a basis for not appointing Mabuza.

"It is proper that Mabuza is appointed the deputy president of the country. It is a culture," she said.

She added that the ANC unity project would collapse if Mabuza was not appointed.