The leaked memo seen by the Telegraph on Thursday said that Corbyn had privately signaled his willingness to make a series of deep concessions if he took charge of the negotiations on Britain’s exit from the 28-member bloc.
The Labour leader met with EU chief Brexit negotiator Michel Barnier in London earlier this week and said he would offer a “unilateral guarantee” on the rights of EU citizens during the transition period, the memo claimed.
The alleged move contrasts with the official Labour policy, which pursues a customs partnership to maintain tariff-free trade in goods across the EU member states' borders.
In a statement later in day, the opposition Labour denied the contents of the memo and said Corbyn merely floated the idea of a new form of customs union.
“Jeremy did not say he was open to staying in the customs union. He said that a customs union was a viable end point. We have been clear all the way through that you can't be in the customs union if you are not in the EU,” it read.
“As for the suggestion that we are trying to undermine the government, it's true that we would negotiate a better deal but it is certainly not the case that we are trying to undermine the negotiations," the statement added.
The memo’s release came as British Prime Minister Theresa May has called on her senior ministers to be "bold" in aiming for a unique post-Brexit relationship with Brussels.
May’s inner Brexit cabinet seem to have made little progress so far in settling the question of what kind of future relationship Britain will seek with the EU after it exits the bloc.
Britain leaves the EU on March 29, 2019, and the bloc insists the transition should last for 21 months until December 31, 2020. The two sides started talks on mechanisms that could govern that phase earlier this week. The draft proposal by the EU Commission stipulates that Britain should be robbed of its powers in decision-making in that period unless a British representative might be able to sit in on EU meetings. It also says that remaining members would have the authority to reintroduce trade tariffs and customs checks in case Britain breaches the terms of the agreement that gives it frictionless access to the single market and the customs union.
Talks on transition period is planned to end in March when the EU and Britain hope to start negotiations on the future of their relations and whether they can nail down an inclusive agreement on trade. An interim deal reached in December outlines guidelines on key separation issues, including how Britain should treat EU citizens after Brexit, what would be the financial settlement and how the Irish border would be treated.
Nearly half of British voters support holding a second referendum on whether the UK should remain or leave the EU amid growing concerns about the government’s Brexit negotiations with the bloc, a poll released in January by The Guardian newspaper shows.