Jami-Lee Ross says National Party leader Simon Bridges is a "corrupt politician", but Mr Bridges says the allegations are "entirely false".
In an extraordinary move, Mr Ross said today he will resign from Parliament and lay a police complaint against Mr Bridges.
Mr Ross alleged Mr Bridges contravened electoral donation law and will lay a complaint with police.
But Mr Bridges said the accusations were baseless and he invited Mr Ross to take them to police.
"We are talking about a guy who is lying, leaking, who is lashing out", he said.
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