Why did MPs who oppose Theresa May’s deal scupper attempts to forge a Commons majority for a soft Brexit?

A blame game has begun at Westminster after MPs from the Independent Group (TIG), the Liberal Democrats and Labour were accused of denying Kenneth Clarke a majority for his plan for the UK to join a customs union.

They were dubbed “purists” and “idiots” by furious soft-Brexit supporters.

Although MPs were allowed to back all four options on their agenda on Monday, some who want a Final Say referendum voted solely for that in order to boost its prospects of emerging as the Commons compromise.

A customs union was defeated by just three votes in a series of indicative votes last night, as the Commons failed for a second time to approve a plan B.

All 11 MPs in TIG, also known as Change UK, voted against both a customs union and the Common Market 2.0 plan for single market membership and a customs arrangement with the EU.

Only one of the 11 Lib Dem MPs, Norman Lamb, voted for a customs union, five opposed it and five abstained, including the party leader Sir Vince Cable. Two Lib Dems, Tim Farron and Lamb, backed Common Market 2.0, four opposed it and five abstained. The single market and customs plan was rejected by 21 votes, and so would also have passed if all TIG and Lib Dem MPs had supported it.

They were not alone: more than 30 Labour MPs who want a referendum abstained on Common Market 2.0. There were claims that some had reneged on a deal under which soft-Brexit backers would vote for a referendum, and similar counter-claims from the rival referendum camp.

A dispute between MPs who favour a single market blueprint and supporters of a public vote has simmered for weeks, and has now boiled over.

The People’s Vote campaign argued that a referendum should not be seen as a rival plan B since it offered a solution to the crisis rather than an alternative Brexit option.

When it came to the crunch, TIG and most Lib Dem MPs decided not to dilute their selling point as a Remain party by voting for options allowing Brexit to go ahead.

TIG MPs said their efforts to draw up a composite motion combining a soft Brexit and referendum were rebuffed. Another attempt may be made in due course by TIG and the Lib Dems, but by then it might be too late.

The senior backbenchers behind the search for a compromise are now devoting their energy to a bill forcing Theresa May to seek to delay Brexit to prevent a no-deal departure on 12 April.

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