Barnier's remarks amounted to a robust defense of the EU single market | Charles McQuillan/Getty Images Michel Barnier: EU won’t break the single market for Brexit UK ‘There will be no unraveling of what we’ve achieved,’ says EU chief negotiator.

We will bend the EU's rules for the sake of Ireland, but don't think for a minute that we will unravel the single market for a departing U.K.

That was the message from a speech by EU chief negotiator Michel Barnier that was billed as an update on the state of the negotiations, but which had a clear subtext for Theresa May as she attempts to win agreement among her divided Cabinet over Brexit.

Asked about the Cabinet get-together at the prime minister's country residence Chequers Friday, Barnier refused to comment directly, saying he would wait for "workable solutions" in the government's white paper next week. But even without engaging directly with May's customs plan — called the "facilitated customs arrangement," under which the U.K. would remain close to Brussels' rules on goods — it wasn't hard to divine what kind of reception it will receive at the European Commission.

Barnier's remarks, at an event organised by the Institute of International and European Affairs think tank in Brussels, amounted to a robust defense of the EU single market — "The heart of the European project," and the EU's "main economic public good," as he put it. It has taken 45 years to build, he said, including the U.K.'s "important and positive role," and with Europe facing so many challenges it has to consolidate its accomplishments.

"There will be no damage to it," said the EU negotiator. "There will be no unraveling of what we’ve achieved."

Barnier lamented the fact that he and his U.K. counterparts are engaged in "negative negotiations."

His decision to emphasize the point on the day of May's "body bag summit" — so named by MPs because of the chance of Cabinet resignations — does not bode well for the prime minister. Under her plan, the U.K. would continue to levy EU tariffs at its borders, but use technology and "trusted trader" schemes to track goods on their journey through supply chains to market. Traders selling goods with lower tariffs destined for U.K. consumers would have the tariffs reimbursed.

In addition, the U.K. would aim to stay in close alignment with EU single market product and manufacturing standards for goods — in order to maintain seamless trade and avoid so-called non-tariff barriers. In short, the U.K. remaining part of some bits of the single market, while not accepting freedom of movement for people.

On the Northern Ireland border, Barnier had a plea to "de-dramatize" the EU's proposed backstop solution to avoid a hard border post Brexit. May has said that no British prime minister could agree to the proposal that would effectively keep Northern Ireland within the EU's customs union.

"Let me be clear. We are not asking for any new borders between Northern Ireland and the rest of the U.K.," said Barnier, "We will obviously need to clarify how and where this control will be done. But ultimately, these are only technical controls on goods. No more, no less."

He acknowledged candidly that the EU has bent its rules to come up with an Ireland plan — though he did not use the phrase "cherry-picking" — but he said such flexibility was motivated by the "unique circumstances" of Ireland and Northern Ireland. "This solution is tailor-made to address the very specific challenges on the island of Ireland," he said.

The negotiator lamented the fact that he and his U.K. counterparts are engaged in "negative negotiations" which are ultimately a "lose-lose game." But he did offer sympathy for May's predicament. "I have ... real respect for Theresa May and I know that her daily work is not so easy,” said the Frenchman.