Brexit talks have finally begun.

Officials negotiating the first departure of a country from the European Union agreed Monday to a framework for discussions that promise to be the most consequential for the United Kingdom since the end of World War II.

Chief U.K. negotiator David Davis and his EU counterpart, former French foreign minister Michel Barnier, told reporters in Brussels that they would first address key questions over how much the U.K. owes the bloc, and the rights of millions of citizens who have settled in Britain or Europe.

They also said their top deputies would immediately begin work on a third issue: How to avoid a "hard border" between Ireland and Northern Ireland that could endanger peace in a region that suffered decades of violence.

"It was clear from the opening that both of us want to achieve the best possible outcome and the strongest possible partnership," Davis said.

But the U.K. gave ground by agreeing that talks on the country's future trading relationship with its largest export market would only take place when the EU decides that sufficient progress has been made on the top three issues.

Davis and Barnier will meet monthly. The U.K. will exit the EU in March 2019 unless all EU nations agree to extend the negotiations.

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A year has passed since voters chose to pull the U.K. out of the EU. And nearly three months have ticked away since Prime Minister Theresa May started the two-year countdown to departure.

The EU has made its opening position clear. Yet Davis entered the talks representing a government in disarray.

A general election wiped out May's parliamentary majority earlier this month and her position has been weakened further in the wake of a deadly fire in a London apartment building. The prime minister is still trying to secure the support of a fringe party whose votes she needs to form a government.

May's hardline EU exit strategy is also being increasingly called into question.

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May had promised to take Britain completely out of the bloc's common trading area and slash the number of people coming from the EU. She even threatened to walk away from Europe without paying a hefty divorce bill or striking a new trade deal, under the mantra that "no deal is better than a bad deal."

But the business community and many lawmakers want to retain closer ties with Europe, and they are heaping pressure on the prime minister to change her approach. One key figure calling for more emphasis on the economy is U.K. Treasury chief Philip Hammond.

"My clear view -- and I believe the view of the majority of people in Britain -- is that we should prioritize protecting jobs, protecting economic growth and protecting prosperity as we enter those negotiations and take them forward," he said last week.

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A coalition of influential business groups echoed that sentiment on Monday, saying that the government should "put the economy first" in the Brexit talks. The group said any deal should minimize trade barriers and include a flexible immigration system.

A poll published over the weekend shows that a slim majority of Britons now want the chance to vote on the terms of Brexit when the talks are concluded.

Davis stuck to May's script on Monday, saying without qualification that Britain would be leaving Europe's single market and its customs union.

Barnier, meanwhile, made clear that a price would have to be paid for the unprecedented split.

"We each have to assume our responsibility and the consequences of our decisions," he said at the conclusion of Monday's press conference. "It's not about punishment, it's not about revenge. We are implementing the decision taken by the United Kingdom to leave the European Union and unravel 43 years of patiently built relations."

Economic data are beginning to lend extra weight to the argument for a softer approach to Brexit.

Consumers, hammered by rising prices and stagnant wages, have snapped their wallets shut in recent months. Political turmoil has caused business leaders to put investments on hold.

The storm clouds began to gather in the immediate aftermath of the referendum, when investors quickly sent the pound to its lowest level in decades over fears that Britain would lose preferential access to Europe's vast markets.

Investors are worried that Britain could crash out of the EU without an exit agreement in place, an outcome that would mean steep new barriers to trade.

"No deal would be a very, very bad outcome for Britain," Hammond said Sunday.

-- Ivana Kottasova contributed reporting.