JEREMY Corbyn is facing a fresh call to explain why Labour MPs voted with Tory politicians in the Commons to block a proposal aimed at preventing a "hard Brexit".

Shadow Chancellor John McDonnell and other opposition frontbenchers opposed an amendment from fellow Labour Edinburgh South MP Ian Murray intended to protect membership of the customs union.

Last night, SNP Westminster leader Ian Blackford hit out at what he said was the "shocking and unbelievable" behaviour of Corbyn's party over the issue.

Blackford has already written to Corbyn asking for an explanation of why Labour helped prop up the Tories in the Commons vote.

However, he said he had yet to hear back from Corbyn as he issued a fresh challenge to him over the issue.

“Labour have some questions to answer. I have written to Jeremy Corbyn, but I have yet to hear back and learn why Labour decided to ignore one of their own member's amendments and instead vote with the Tory Brexiteers," he said.

"It was shocking and unbelievable to witness Labour MPs voting against, or abstaining, on a perfectly sensible amendment tabled by a Scottish Labour MP to try and stop the worst excesses of a cliff-edge hard Brexit.

"It was particularly shocking that amongst those voting against were the Shadow Chancellor and the Labour front bench Treasury team. That is something they will have to explain.

"The SNP supported the amendment because we firmly believe that remaining in the single market and the customs union is clearly the least damaging Brexit option. Leaving the single market and the customs union will have disastrous effects, costing jobs and hitting our economy.

"I have asked Jeremy Corbyn to clarify Labour's position on the vote. Was it an instruction from him as party leader and if so what is his position on the UK leaving the customs union?"

A Labour spokesperson, hitting back, said: “This amendment was not about whether we stay in the customs union. Labour has been clear that we would seek to remain in a customs union during a transitional phase and that a customs union is a viable long-term option, subject of course to negotiations.

“We have also emphasised that our priority for Brexit negotiations is ensuring tariff-free trade with the EU. The trouble with this amendment is that it comes before trade negotiations have even started.

"Labour will continue to fight for a Brexit deal that protects jobs, the economy and rights but no responsible government or opposition could support this motion.”

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