A struggle for Parliament's Speaker this afternoon, even with only nine MPs allowed in the debating chamber.

It was removing his mask to bring Act's David Seymour into line that caused Trevor Mallard a spot of bother.

Seymour was told if he was deliberately interrupting Jacinda Ardern with an invalid intervention it'd be serious for him.

The Act leader complained she'd been taking a long time to reply to a question ... which saw Mallard becoming entangled in his mask and hearing aids.

Mallard ruled in favour of the Prime Minister and told Seymour he'd deny him further questions if be misbehaved again.