Michelle O'Neill has said Ian Paisley must resign over his failure to declare two family holidays paid for by the Sri Lankan government.
Speaking this afternoon, the Sinn Féin deputy leader said the North Antrim MP's behaviour was "disgraceful".
Mr Paisley is facing a 30-day suspension from Westminster and a possible by-election after the Parliamentary Commissioner for Standards found he had breached rules on how MPs register financial interests.
"His behaviour is disgraceful. It is not acceptable," she said.
"It is not befitting of public office to receive...an all-expenses-paid holiday and then not declare it isn't acceptable. That is not the standard that people expect from anyone who holds public office. So I think his behaviour is absolutely atrocious and I don't think an apology is acceptable."
When asked if Mr Paisley needed to resign, Ms O'Neill replied: "Yes he does".
Read more:
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- Ian Paisley has made headlines before for all the wrong reasons
- What did the lavish Sri Lanka trips cost?
- Video: Emotional Ian Paisley apologises in House of Commons
- How the scandal unfolded
- Analysis: Ian Paisley's actions spell all kinds of trouble (premium)
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