Donald Tusk said Theresa May needed to put forward “concrete proposals” if she wanted to avoid a no deal, after it emerged that leaders will not even consider plans for a trade deal with the UK because of the impasse.
The prime minister is due to address EU leaders on Wednesday ahead of a dinner where they will decide whether or not talks have run out of road.
Negotiations on the Irish border came to a dramatic halt on Sunday after signs that a breakthrough was close proved to be a false start.
“Unfortunately the report on the state of the negotiations that I got from Michel Barnier today, as well as yesterday’s debate in the House of Commons, gives me no grounds for optimism before tomorrow’s European Council on Brexit,” Mr Tusk told reporters at a press conference.
“As I see it, the only source of hope for a deal for now is the goodwill and determination on both sides. However, for a breakthrough to take place, besides goodwill we need new facts.
“Tomorrow I am going to ask Prime Minister May whether she has concrete proposals on how to break the impasse. Only such proposals can determine if a breakthrough is possible.”
Mr Tusk said European countries needed “to make sure that we are prepared in case an agreement is not possible or in case it is rejected” and said leaders would step up no-deal preparatory discussions tomorrow.
The 27 EU leaders will not even consider a trade deal with Britain at the summit, following the collapse of the border talks this weekend.
The shock revelation, confirmed by senior EU diplomats familiar with preparations for the meeting, shows the rising risk of a no-deal Brexit as Theresa May travels to the EU capital in a bid to save her project.
Over dinner on Wednesday night the heads of government will decide whether there is any point in holding a special Brexit summit in November or whether the horse has already bolted and they should step-up preparations for a no deal.
But they will not be presented with any drafts of the “joint political declaration” on the future relationship – the outline of a possible trading relationship between the UK and EU. Brussels has long insisted a trade deal can only be considered once withdrawal issues like the Irish border are settled.
“The agreement on the withdrawal agreement, the Irish backstop, would trigger the delivery of the outline of the joint political declaration. That outline was supposed to be drafted by the Commission and would form the basis of the discussion of the EU leaders tomorrow evening,” one senior EU diplomat said, speaking in Brussels ahead of the meeting.
“Since there is no agreement on the withdrawal, including on the Irish backstop, there will not be an outline of the joint political declaration on the table on Wednesday evening. That’s the situation as it stands and it will not change before Wednesday.”
The lack of discussion about the future relationship is a huge blow for the prime minister, who has said she needs detailed plans on trade to get any withdrawal agreement – including on the multi-billion pound divorce bill – past MPs. Her Chequers proposals were rejected out of hand by EU leaders as unworkable last month in Salzburg, after months of hints by the European Commission that they would not fly.
The diplomat added: “The truth is… we have clarity now, actually, more clarity than we had in Salzburg. What we have found out in the process leading to this meeting on Wednesday is that it is not going to be so easy to find a deal between the EU and the UK.”
The prime minister will once again be barred from the main discussion of Brexit at the summit, and will have to address the 27 leaders ahead of their dinner in a separate room.
Ms May will also have to share her platform with Antonio Tajani, the European Parliament president, who has been given the opportunity to put the body’s views to leaders ahead of their decision. Officials familiar with preparations said it was likely that Mr Tajani would be allowed to speak before the prime minister.
The 27 other leaders will then go into their dinner, where they will hear chief negotiator Michel Barnier’s recommendation and draw their “moment of truth” conclusions.
The prime minister will have to find her own dinner. One EU source confirmed there would be “no food on the table” at the meeting with Ms May, and that the meeting afterwards would take the format of a dinner because it “will take place at the time when normally people have dinners”.
One EU diplomat was confident that the 27 national leaders would be unlikely to overrule Mr Barnier.
“They meet primarily to decide on the further steps in the Brexit negotiations on the basis of our report of our negotiator Michel Barnier,” the diplomat said.
“I can tell you that my impression is – and as you know I’m listening to those summits, I’m in the room when those discussions amongst the leaders take place – my impression is that with every summit the trust of Barnier and the support of Barnier [from the leaders] only increases.”
Gernot Blumel, Austria’s Europe minister, who chaired an EU Council meeting on Tuesday, told reporters that the 27 member states were united behind Mr Barnier and that such an approach was “absolutely key for the successful outcome of the negotiations”.
In Salzburg the leaders resolved only to hold a Brexit summit in November if a deal with the UK looked on the horizon and there had been “decisive” progress.
It comes as pressure mounts on the prime minister from her own party to water down her offer to the EU and put an end date on the Northern Ireland “backstop” plan that would keep Britain tied to the EU customs union.
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