(Bloomberg) -- Prime Minister Theresa May isn’t the only U.K. political leader with a party that’s divided and increasingly belligerent over Europe. Jeremy Corbyn’s opposition Labour is in a similar bind.

His spokesman said it would be “impossible” for Labour to be as split on the issue as May’s Tories. The official party line on Brexit has been shifting toward having closer ties with the European Union with an eye to toppling May.

Yet this week’s marathon Brexit debate have Labour members of parliament concerned about their Brexit-voting electorates -- and pro-European lawmakers frustrated by Corbyn’s euroskeptic history -- airing their frustrations in full view.

It’s tradition in Parliament not to accuse other members of telling lies, but shadow Brexit spokesman Matthew Pennycook came close on Tuesday -- and got into trouble with the Speaker -- when he accused two colleagues on his side of being “disingenuous.”

Frank Field, a veteran lawmaker from the northwest of England, was his first victim after suggesting the point of the amendment Pennycook was backing was to stop Brexit, then Gareth Snell, who represents Stoke-on-Trent in the Midlands, got the same treatment for making a similar point.

Snell broke cover on Monday to accuse other lawmakers who support staying in the European Economic Area of falling for a “quick fix” and stoking voters’ mistrust in an article for the Labourlist website.

Insulted

Remaining in the EEA -- basically staying in the single market and accepting EU’s rules -- would force Britain to accept EU immigrants, he said, and that’s why many people voted to leave the bloc. Caroline Flint added her voice, saying her constituents have been “insulted” by people who favor the continued free movement of labor.

Chuka Umunna, a pro-EU colleague, told lawmakers that opposition to immigration should be met “in a Labour way” -- as it was when some of the party’s working-class base objected to immigrants from the Caribbean and Africa in the 1960s. The government should be investing more in housing, the health service and education to relieve pressure on services, he said, not ending free movement of labor.

The Labour whips -- who enforce discipline in the party -- instructed lawmakers on Wednesday to abstain on an amendment favoring membership of the EEA and introduced their own, more vague version.

Defying the Whip

Hilary Benn, whose father was Corbyn’s political mentor, said he would break with the whips’ instructions. “I’ll vote for the EEA amendment because we need to keep our options open,” he told lawmakers.

The Corbyn leadership knows it’s got a battle on its hands to stop the divisions consuming the parliamentary party, which is already split over support for Corbyn. But it also knows that Labour’s divisions on Europe are eclipsed by the divisions on the other side of the aisle. They are, after all, not in government.

“We are walking on a tightrope at the moment, we campaigned for remain but many of our MPs, including myself, now represent seats which voted heavily leave,” John McDonnell, the party’s economy spokesman and Corbyn’s right-hand man said at an event in London on Wednesday. “We are trying to construct at the moment a traditional British compromise and we are trying to drag as many with us as possible both in government and elsewhere around some key elements of that compromise.”

--With assistance from Jessica Shankleman.

To contact the reporter on this story: Thomas Penny in London at tpenny@bloomberg.net

To contact the editors responsible for this story: Flavia Krause-Jackson at fjackson@bloomberg.net, Michael Winfrey

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