The first substantive round of Brexit negotiations ended Thursday with the EU and U.K. deadlocked on core divorce issues, leaving officials openly pessimistic about meeting an October deadline for moving on to the next phase of talks.

Officials hoped for a lightning-quick deal on the rights of EU citizens living in the U.K. and vice-versa — an area where they envisioned broad agreement — so they could show constituents forward momentum before the summer break. Instead, they came up empty, and Brussels and London seem even further apart than ever.

Britain not only flatly rejected the EU's demand that it offer a methodology for computing the financial settlement, as the EU did, but the U.K.'s lead negotiator David Davis refused to even acknowledge the ultimate calculation of the so-called Brexit bill would lead to a net payment to Brussels from London.

"We are a country that recognizes its international responsibilities and rights," Davis said at a news conference with the EU's chief negotiator Michel Barnier. But Davis added pointedly: "I don't recognize the phrase 'net flow,'" referring to a question about payments to Brussels after Brexit. Barnier similarly expressed little willingness to give ground on any of the major divorce issues.

At their news conference, the negotiators seemed testy and ill-at-ease. And far from showing the two sides striving toward a mutually beneficial deal, this week's meager results made clear this is not a negotiation among friends, as the sides had professed, but a contest of adversaries seeking advantage at each other's expense.

A British official said there would be no estimate of the Brexit tab (which Brussels says could total €100 billion) agreed on before the October European Council summit in Brussels.

Instead of proposing their own methodology for the financial settlement, U.K. negotiators spent this week quizzing the EU side about its proposal.

“The requirement for October is sufficient progress," one British official said after the talks had ended. "It’s not settling the financial settlement. In some places there has been a bit of a misunderstanding about that.”

But Britain's position on the financial settlement left EU diplomats shaking their heads and voicing deep pessimism about the prospects of reaching that "sufficient progress" — moving on from the divorce phase to discussions about a future trade relationship.

Instead of proposing their own methodology for the financial settlement, U.K. negotiators spent this week quizzing the EU side about its proposal.

One person familiar with the British position said the U.K. side believed negotiators accepted the reality that London won't have any settlement figure for them by October, nor even a formula to get to a figure, because it would be “politically impossible" for Prime Minister Theresa May to present a bill to the British public before she has anything in the way of trade commitments or other upsides to show for it.

The view could not have been more different on the EU side, where officials slammed the U.K. for trying to avoid a discussion on financial obligations that Brussels regards as self-evident and indisputable.

"The Brits don’t want to enter into discussion because they know that at the end of the day it is going to be difficult to contest the very existence of budgetary and legal commitments," a senior EU diplomat said.

A senior EU official complained: “We cannot have a serious discussion on the financial settlement as long as we do not have a clarification on where the U.K. stands." By contrast, this official said British negotiators "had a long set of questions, and we were able to answer each one of them.”

Extra rounds

Another senior EU diplomat raised the possibility that two more rounds of negotiations might need to be added to the monthly sessions scheduled in August, September and October to prevent the talks from collapsing.

At the news conference, Barnier complained that the U.K. thwarted his hopes of identifying areas of agreement and disagreement in this week's talks, and that Britain's goals in the negotiations remained obscure.

“I said last week that I wanted to identify the points where we agree and the points where we disagree,” Barnier said. “This was possible this week for the issues on which there was a clear British position.”

But he quickly made clear that there was not sufficient clarity. On the question of a financial settlement, Barnier said sharply: "A clarification of the U.K. position is indispensable for us to negotiate and for us to make sufficient progress on this financial dossier, which is inseparable from the other withdrawal dossiers."

On citizens' rights, negotiators were at a stalemate over the EU's demand that any future disputes be adjudicated by the European Court of Justice (ECJ) — the EU's highest court in Luxembourg.

A British official complained after the close of the talks that the EU’s demand on the ECJ represented an “unprecedented” attempt to impose a foreign court’s will on a third country. And irritation was running high at what some in London consider to be “judicial imperialism” on the part of the EU.

“We had robust but constructive talks this week. We shouldn't expect incremental progress in every round” — David Davis

While the U.K.'s opposition to a role for the ECJ was well-known, new disputes on citizens' rights emerged this week, including over a demand by the British side to conduct criminal background checks on the more than 3 million EU citizens residing in the U.K. if and when they request to stay under any Brexit agreement. The U.K. also claimed that denying freedom of movement rights to its citizens on the Continent post Brexit amounted to unfair treatment.

New issue

The U.K. at one point also tried to inject a new issue into the citizens’ rights debate, raising the issue of posted workers, to the annoyance of the EU side. It viewed the move as trying to fast-forward the discussion on a future trade relationship because such temporary workers typically do not face the residency issues of citizens permanently living and working outside their home country.

Those disagreements undermined efforts to show at least some progress.

For instance, on citizens’ rights, negotiators had drawn up a traffic light system aimed at illustrating how they are doing, British officials said. Out of 44 separate issues, they marked eight as yellow, 14 as red and 22 as green — meaning there was consensus on half of the file, but still a long way from a quick deal.

There was also essentially no progress at all on the complex questions surrounding Ireland and its border with Northern Ireland, as well as the particular concerns related to protecting the Good Friday Agreement — a goal that each side has said should be of paramount importance.

Barnier offered a bleak assessment, saying the Ireland question "in all its dimensions requires more detailed discussions."

At the news conference, Davis tried to put a positive spin on things. “We had robust but constructive talks this week,” he said, adding, “We shouldn't expect incremental progress in every round.”

On that last point at least, there seemed to be no dispute.