Barnier: 'Not a minute to lose on Brexit talks' after customs union confirmation

The EU's chief Brexit negotiator Michel Barnier is meeting the Prime Minister and his UK counterpart in Downing Street.

Setting off on a cross-Channel train this morning, he told Sky News: "We haven't a minute to lose because we want to achieve a deal."

His visit comes at the start of a week of crucial negotiations within the EU and the Cabinet, and hours after Downing Street insisted Britain will "categorically" leave the customs union.

Seeking to calm the fears of some backbench critics who have accused Chancellor Philip Hammond of trying to pursue his own policy aimed at keeping Britain as closely aligned as possible with the EU, a No 10 source said last night: "It is not our policy to be in the customs union."

The source said they would be seeking an "arrangement" with the EU to ensure trade remained as "frictionless" as possible after Brexit.

Reacting to the confirmation, Mr Barnier said earlier: "We know the line of the Government... We have to respect the red lines of the British Government - but they have to respect the rules of the Union."

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Officials are preparing to open negotiations on transitional arrangements.

Today's talks in Downing Street will mark the first time Mr Bariner, Mrs May and Mr Davis have met since EU leaders gave the green light for the second phase of negotiations to start at their December summit in the Belgian capital.

Fresh tensions have emerged after the European side insisted that EU law must continue to apply in the UK throughout the post-Brexit transition period - expected to last about two years.

Mrs May has already made clear that she intends to push back against the bloc's demands that EU citizens who come to the UK during the transition should enjoy the same rights as those who come before Britain leaves the EU on 29 March 2019.

Ministers have said the demand goes beyond what was agreed at the December summit but senior EU figures insist it is "not negotiable".

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The meeting will be followed on Tuesday by the first technical discussions by UK and EU officials in Brussels on the transition arrangements, which are intended to ensure businesses and citizens are not faced with a "cliff-edge" break when Britain leaves the bloc.

Meanwhile, senior ministers are also preparing for the first discussions on Britain's future relationship with the EU by Mrs May's so-called "Brexit war Cabinet".

Members of the Cabinet Brexit sub-committee will meet on Wednesday and then again on Thursday as they seek to thrash out an agreement on thorny issues such as customs arrangements with the remaining EU27.

The subject is so sensitive that the Prime Minister has previously declined to authorise any formal discussion in the group.

On Sunday, Home Secretary Amber Rudd brushed aside warnings from hardline Brexiteers that Mrs May could face a leadership challenge if she fails to deliver a "clean Brexit".

Ms Rudd said ministers would not be intimidated and insisted that there was greater agreement around the Cabinet table than MPs (BSE: MPSLTD.BO - news) sometimes realised.