Labor claims it has dealt an “embarrassing blow” to Malcolm Turnbull by forcing a government backbencher to cross the floor of parliament on penalty rates.

The opposition gained the support of Nationals MP George Christensen on Tuesday night when he crossed the floor on an amendment that would have prevented cuts to Sunday penalty rates for some workers.

But the move was defeated 73-72.

Opposition employment spokesman Brendan O’Connor says Labor will relentlessly pursue the Fair Work Commission decision which will be phased in from July 1.

“If the government thinks that this matter is over when we rise at the end of this week, they are mistaken,” O’Connor told reporters on Wednesday.

Labor will campaign across the country during the parliamentary winter break.

“It’s one thing to be thinking about a cut that will happen; once cuts start to happen and the effects are real, this changes fundamentally,” he said.

“We won’t be talking about workers who may be losing money, we’ll be talking about workers that (sic) have lost money that can’t pay the rent, can’t pay for bills.”

O’Connor called on Victorian independent MP Cathy McGowan to reconsider her position and back Labor’s push.

Greens MP Adam Bandt was pleased a “snowball” seems to be growing behind the minor party’s position to lock in penalty rates.

“We are now only a vote or two away in this parliament from stopping the penalty rate cuts from coming into effect,” he said.

Fast food, hospitality, retail and pharmacy workers will see their Sunday penalty rates drop five percentage points on July 1.

The full cuts of 25-50 percentage points will be imposed on some workers by 2019 and for others by 2020.

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