BRUSSELS -- The European Union and Britain inched ever closer to a tentative Brexit deal on Wednesday, with the leaders of France and Germany saying they expected a deal could be sealed at the upcoming EU summit.

Positive vibes oozed from French President Emmanuel Macron and German Chancellor Angela Merkel at a joint news conference in Toulouse, France.

Merkel said “we are in the final stretch,” while Macron said “I want to believe that a deal is being finalized and that we can approve it” Thursday, when EU leaders are due to meet Johnson in Brussels.

British Prime Minister Boris Johnson, meanwhile, likened Brexit to climbing Mount Everest, saying the top was in sight, though still shrouded in cloud.

With just hours to go before the EU summit, hopes were increasingly turning toward getting a broad political commitment, with the full legal details hammered out later. Negotiators were locked in EU headquarters with few details leaking out. Wild movements in the British pound on Wednesday underscored the uncertainty over what, if anything, might be decided.

Meetings between EU Brexit negotiator Michel Barnier and key EU legislators as well as with ambassadors of the member nations were rescheduled for the evening - an indication there was still momentum in the ongoing talks among technical teams from both sides.

“It looks like things are moving,” said an EU official, who spoke on condition of anonymity because talks were still ongoing.

British Prime Minister Boris Johnson's spokesman, James Slack, echoed that, saying there is still “a chance of securing a good deal” at the summit, even though a number of issues remain.

The thorniest among them is how goods and people will flow across the land border between EU member Ireland and Northern Ireland, which is part of the U.K.

So far all plans to keep an open border have hit a brick wall of opposition from Johnson's key Northern Irish ally, the Democratic Unionist Party. DUP leaders met several times with the British leader Wednesday as he tried to win their support. Without it, any Brexit deal is likely to be rejected by Britain's Parliament.

Johnson told Conservative Party lawmakers on Wednesday that he believed a deal was close.

Legislator Bim Afolami quoted Johnson as saying “the summit is in sight, but it is shrouded in cloud. But we can get there.”

Northern Ireland is not the only issue. An eventual withdrawal agreement would be a legal treaty laying out the terms of Britain's departure and setting up a transition period in which relations would remain as they are now at least until the end of 2020, to give people and businesses time to adjust to new rules. It will guarantee the rights of EU citizens in Britain, and British nationals living elsewhere in the EU, to continue with their lives.

But it leaves many questions about the future unanswered, and Britain's departure is sure to be followed by years of negotiations on trade and other issues.

Even if a provisional deal is inked this week, moves in the British Parliament could still mean another delay to Britain's departure, currently due to take place on Oct. 31. It also raises the prospect of another EU Brexit summit before the end of the month.

“The 31st of October is still a few weeks away, and there is a possibility of another summit before that if we need one,” Irish Prime Minister Leo Varadkar said in Dublin.

Adding to the pressure and uncertainty is that any deal must be approved by the British Parliament, which has already rejected agreements three times and has also issued an order that Johnson's government must seek to delay the departure if a deal isn't in place by Saturday.

The British government continues to insist the U.K. will leave on Oct. 31 - but also promises to obey Parliament's order.

With the need to get Parliament's approval looming over negotiations, EU leaders are seeking reassurances from Johnson during this week's summit that he has the political weight to push any new deal through the House of Commons, which is due to meet on Saturday for its first weekend session in almost 40 years.

The Brexit talks plodded ahead Wednesday, further delaying preparations for the EU summit. Since the weekend, negotiators have been locked in long sessions on how to deal with detailed customs, value-added tax and regulatory issues under British proposals to keep goods and people flowing freely across the border between Northern Ireland and Ireland.

“Talks have been constructive, but there still remains a number of significant issues to resolve,” EU Commissioner Dimitris Avramopoulos said after being briefed by EU Brexit negotiator Michel Barnier.

Johnson is eager to strike a deal at Thursday's summit that will let the U.K. leave the bloc in good order on Oct. 31, fulfilling his promise to get Brexit done. But he has also vowed to leave the bloc deal or no deal.

U.K. lawmakers, however, are determined to push for another Brexit delay rather than risk a chaotic no-deal Brexit that economists say could hurt the economies of both the U.K. and the E.U.

Beyond the questions of disrupting to daily life, an open Irish border underpins both the local economy and the 1998 peace accord that ended decades of Catholic-Protestant violence in Northern Ireland. But once Britain exits, that border will turn into an external EU frontier that the bloc wants to keep secure.

The big question is how far Johnson's government is prepared to budge on its insistence that the U.K., including Northern Ireland, must leave the EU's customs union - something that would require checks on goods passing between the U.K. and the EU.

The alternative is to have checks in the Irish Sea between Britain and Northern Ireland. But Northern Ireland's DUP, the party that props up Johnson's minority Conservative government, strongly opposes any measures that could loosen the bonds between Northern Ireland and the rest of the U.K.

Pro-Brexit Conservative British lawmaker David Davis said success in passing a Brexit deal rests on the stance of the DUP.

“If the DUP says 'This is intolerable to us' that will be quite important,” he said.

DUP leader Arlene Foster said the party had not yet consented to a deal. She tweeted: “Discussions continue. Needs to be a sensible deal which unionists and nationalists can support.”

Lawless reported from London. Mike Corder and Gregory Katz contributed from London, Lorne Cook and Sam Petrequin from Brussels.