(Bloomberg) -- European Union leaders are poised to turn their next summit into a Brexit crisis meeting, just two days after Prime Minister Theresa May faces almost certain defeat in Parliament over the divorce deal. But so far, they’re not willing to offer her anything that could shift the parliamentary math.

According to EU officials, leaders are waiting for May to tell them what she needs. What they do will also depend on the scale of her defeat. Some last-minute rescue options are already being discussed, and it’s not impossible that negotiators will get round the table again, according to one EU official who declined to be named.

While Europe’s leaders will stick to the message that they will not renegotiate the deal and will ramp up preparations for the U.K. crashing out without an agreement, they may also consider:

  • rewording some of the non-binding draft agreement on the future economic relationship;
  • delaying Brexit day -- but probably only if May indicates that a second referendum on EU membership is a real possibility;
  • beefing up verbal commitments on how the EU will try to avoid applying the Irish border “backstop.”

These choices will be shaped by May’s assessment of the situation, and what she thinks the EU should do next, the officials said. The EU is unclear about what will help get British lawmaker support and it’s up to May to clearly spell out what she needs, they said.

As May is widely expected to face a humiliating rout on Tuesday, speculation is mounting that she might postpone or pull the vote. Graham Brady, the chairman of rank-and-file Conservative lawmakers, hinted on Thursday that the prime minister should delay the vote a few days and seek concessions from Brussels at the summit first.

In the days before the vote, May is trying to win over lawmakers on both sides of the Brexit divide who criticize her agreement for keeping the U.K. shackled to the EU indefinitely. The trickiest bit of the contract is the Irish backstop plan, which started out as a guarantee to avoid a border on the island of Ireland and has ended up as a potentially permanent state of quasi-membership for the whole U.K.

Merkel Firm

German Chancellor Angela Merkel and French President Emmanuel Macron have been clear they have no intention of re-opening the draft deal agreed two weeks ago after 17 months of talks. Officials said EU leaders will reiterate that stance.

Hinting at the type of message the summit might send the U.K. next week, the EU’s chief Brexit negotiator, Michel Barnier, said that the backstop arrangement wasn’t satisfactory even to the bloc.

“We will do everything to not have to use this backstop,” he said on Thursday.

Neither side has got anything up their sleeve to help May return from Brussels with a package to win over lawmakers in a second vote, one official said. And while a loss for May on Tuesday would send shockwaves through European capitals, there won’t be time before the start of the summit on Thursday for officials to revise the deal, a separate official said.

It’s not even clear if it will be May heading to Brussels on Thursday -- depending on the scale of the defeat.

To contact the reporter on this story: Ian Wishart in Brussels at iwishart@bloomberg.net

To contact the editors responsible for this story: Ben Sills at bsills@bloomberg.net, Emma Ross-Thomas, Zoe Schneeweiss

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