(CAPE TOWN) -- The mayor of Cape Town, Reverend William Bantom, was forced to resign on Tuesday after admitting to downloading pornography from the Internet, his New National Party said.

``I have demanded his resignation from the New National Party with immediate effect,'' Western Cape Premier Gerald Morkel told reporters. ``His resignation from the NNP will also inevitably require him to resign as mayor as well.''

``I know I have done wrong and I respect the wishes of my party in asking me to resign,'' the South African Press Association quoted Bantom as saying.

Bantom was Cape Town's first black mayor.

``I have erred...and I pray that my fellow Christians and the community will find it in their hearts to forgive me,'' he said.

Morkel said Bantom, mayor of the Cape Metropolitan Council, had been caught in his office watching pornographic videos -- including at least one involving children performing sex acts with adults -- that he had downloaded from the Internet.

Bantom had been a candidate for the Democratic Alliance, a party formed by a merger between the Democratic Party and the New National Party, in municipal elections that are set for November and which will be hotly contested in the province.

Both the two main South African television channels led their evening bulletins with the news of Bantom's resignation.