South Africa's deputy president Phumzile Mlambo-Ngcuka handed in her resignation on Monday, after President Thabo Mbeki bowed to ANC party pressure to step down, her spokesman said.
"She has handed in her resignation as deputy president to the outgoing president, she has also handed in her resignation as member of parliament," said spokesman Denzil Taylor.
He told independent television Etv News that Ngcuka believed the new president should be allowed the chance to choose his own deputy, and also cited "personal reasons" for her resignation.
"The deputy president's resignation coincides with that of the president."
Mlambo-Ngcuka took the post of deputy president in 2005, when Mbeki axed Jacob Zuma from the post after he was implicated in corruption allegations.
Zuma has faced corruption charges for seven years, but the latest bout of allegations were thrown out of court earlier this month in a ruling that hinted that Mbeki had interfered in the decision to prosecute him.
The judgement led to the African National Congress calling for Mbeki to resign.