The Democratic Alliance was shocked that former African National Congress chief whip Tony Yengeni would display "further contempt for parliament" by attending its proceedings a day after admitting in court that he had defrauded the institution, party spokesperson Raenette Taljaard said on Friday.

Yengeni was among the ANC parliamentarians who attended President Thabo Mbeki's state of the nation address.

"While Mr Yengeni may be on a political winning streak with his party, having recently been elected to the ANC's national executive committee, his behaviour towards the institution of parliament should mean an end to his political career," Taljaard said in a statement.

Even if Yengeni's eventual sentence was to fall short of the Constitutional provision which would bar him from parliament, the ANC should remove him, as he was an embarrassment.

"If Mr Yengeni had any dignity or remorse about his actions, he would have displayed both the common sense and good judgement to resign or, at the very least, stay away from today's proceedings.

"Instead he was highly visible and certainly not displaying any signs of remorse."

Taljaard urged the ANC leadership to "stop ducking the issue" as they had done in parliament's ethics committee in 2001, and to deal with Yengeni.

Earlier on Friday, Yengeni took his seat as a backbencher.

He was seated next to ANC MP and chairperson of the National Assembly's justice committee Johnny de Lange, and behind ANC MP Winnie Madikizela-Mandela whose trial is still continuing.

Yengeni was convicted of fraud on Thursday by a Pretoria magistrate in terms of a plea agreement with the state.

In return, he was acquitted of corruption. The charges relate to a 47 percent discount he received on a luxury 4X4 Mercedes Benz in 1998.

In a written explanation handed up to Pretoria's commercial crimes court, Yengeni admitted he acted in breach of his public duties and with the intent to defraud parliament.

Yengeni is expected to be sentenced next week, and in terms of the Constitution will only have to vacate his parliamentary seat if he is jailed for more than a year without an option of a fine.

Asked for reaction, ANC spokesperson Khulekani Ntshangase said on Friday: "The DA's statement is not worth any comment from the ANC."

The ANC will reportedly decide Yengeni's future at a meeting of the party's national working committee in two weeks.

With acknowledgements to Sapa and Independent Online.