Labour deputy-leader Harriet Harman ordered David Cameron to "man up" over press regulation today, warning her party would not support "watered-down" plans.
Ms Harman said Labour wanted to reach an agreement with the coalition and avoid a political spat over the issue.
Earlier this month the Tories unveiled their proposals for a press regulator protected by a royal charter.
But Ms Harman mocked the charter today as a "Byzantine idea" and urged the Prime Minister to "stop being pushed around by some aspects of the press."
She said that Labour would rather seek a cross-party agreement over press regulation, which could include both a royal charter and new laws, but predicted Leveson-style laws could be pushed through the Commons in a vote.