South African Rugby confirmed the exit of the Cheetahs and Southern Kings from Super Rugby in 2018, as the teams revealed they will explore "other international competition opportunities", with a move to the Guinness Pro 12 looking likely now.

The axing of the pair was widely expected as SA Rugby cut the number of its Super Rugby teams from six to four.

The duo had already informed SA Rugby they were looking at alternative international competitions before Friday's axing was ratified by SA Rugby's General Council.

I want to thank the Cheetahs and the Kings for the mature and professional manner in which they approached and managed this difficult situation. They took decisions that will not only benefit them, but also SA Rugby in general, SA Rugby CEO Jurie Roux said in a statement.

The Cheetahs had an agreement with SA Rugby to compete in the southern hemisphere's Super Rugby until 2020 but announced earlier on Friday they had reached a settlement to exit early.

Along with the Kings, they are tipped to join the Pro 12 for the 2017-18 season.

Although the move has yet to be formally announced, Cheetahs CEO Harold Verster suggested the team had secured entrance into an alternative international competition.

"It will be an exciting challenge for our players, supporters and commercial partners, and will be the start of a new chapter for rugby both in our region and in South Africa," Verster said.

"Also, it will allow the Cheetahs to carve out a new and prominent place on the rugby map in South Africa as well as internationally."

Andre Rademan, president of the Eastern Province Rugby Union that provides a home base for the Kings, also hinted they would be joining a new, unnamed competition soon.

"There is now a clear and viable way forward for rugby in the Eastern Cape to build on the foundations that have been laid - particularly in the past season," he said.

"We have enjoyed Super Rugby but the chance to test ourselves against different opposition in different conditions is a mouth-watering one. We are therefore not opposed to joining new competitions."

Neither the Cheetahs nor the Kings are in contention for a playoff spot in this year's Super Rugby competition.

The Super Rugby competition is being cut from 18 to 15 teams overall next year after complaints from broadcasters over the format of the current tournament.

Australia will lose the other team, with either the Melbourne Rebels or Western Force facing the axe.