Prime Minister Scott Morrison is under pressure to rebuke a government backbencher for spreading misinformation about coronavirus.

Liberal MP Craig Kelly has been promoting unproven cures on social media and last week likened mask mandates for school students to child abuse.

With Mr Morrison back at work on Monday after a week-long holiday, the Labor party is demanding he censure his party-room colleague.

“Labor condemns Craig Kelly for spreading misinformation in a pandemic. It’s on all of us as leaders to call it out,” opposition leader Anthony Albanese said.