South African President Cyril Ramaphosa, re-elected for a second term after his weakened ANC lost its outright majority, will announce an "inclusive" cabinet, the party said Saturday.

The African National Congress (ANC) said Ramaphosa, who will lead what it calls a government of national unity, will announce an "inclusive" cabinet after the May 29 general election produced no outright winner.

Congratulatory messages continued to pour in for the leader who was re-elected as president on Friday and will be inaugurated on June 19.

US President Joe Biden also congratulated Ramaphosa, adding that he looked forward to the two countries "continuing our work together".

The election marked a historic turning point for South Africa, ending three decades of dominance by the ANC of the late Nelson Mandela.

The humbled ANC said it was "ready to set aside our political differences, find innovative ways to work together in the interest of our nation".

The national unity government includes the centre-right Democratic Alliance (DA), the Zulu nationalist Inkatha Freedom Party and other smaller groups.

On Friday Chief Justice Raymond Zondo had opened the parliament's first sitting, swearing in MPs in batches and presiding over the election of the speaker, who was from the ANC, and a deputy speaker who hailed from the DA.

However, South Africans continued to express scepticism about the unprecedented deal, particularly the union of long-term political foes the ANC and the DA who have been the country's longest official opposition.