There will be no bartering over the amount the UK will have to pay as it exits the EU, France's finance minister has told the Irish Independent.
In an interview ahead of his visit to Dublin today, Michel Sapin said the EU and UK will have to come to mutual agreement about how to calculate what the latter owes.
But he warned that if there are no signs that the UK is willing to reach agreement, it won't be possible to put together a good deal.
He also said the EU has no intention of punishing the UK or taking a tough stance with the country in the negotiations, but added the decision to leave has consequences.
Britain is facing a bill of about £50bn (€58bn) as it prepares to exit the EU, according to Commission President Jean Claude Juncker, with the formal exit process set to begin on Wednesday when Prime Minister Theresa May triggers Article 50. The size of Britain's exit bill will be among the first - and most contentious - topics for discussion, with British ministers indicating they do not believe the UK is liable for such a large sum.
Mr Sapin told this newspaper that he was optimistic that an arrangement can be found.
"This is not about getting the UK to pay for its decision to leave, but rather doing the sums and working out exactly what it owes under the terms of its budget obligations as an EU member state," Mr Sapin said. "It is an extremely complex issue, so we need to reach a mutual, unequivocal agreement about how we calculate the UK's dues.
"But there is no question of bartering over specific figures. That is not how it works. [European Commission Brexit negotiator] Michel Barnier has made that quite clear. Obviously, if there are no signs that the UK is willing to reach an agreement on these issues as it leaves the EU, we will not be in a position to negotiate a good deal for the future. But I am genuinely optimistic that we will come to an arrangement."
More generally, he said the task was now to reach a deal that works for everyone, acknowledging that Brexit raises "particularly challenging" issues for Ireland which he said will have to be taken into account in the negotiations.
"The EU has no intention of taking a tough stance or punishing the UK. That does not serve anyone's interests," he said. "But being a member comes with regulatory obligations and other duties. The British people have decided, of their own free will that they want to leave. We deeply regret that choice. But everyone understands that the decision has consequences."
He also said he believed Paris had the potential to become the Eurozone's premier financial hub. He said financial services firms are already looking to leave London, noting HSBC's decision to shift 1,000 jobs to Paris. Dublin is tipped as a possible contender for financial services jobs displaced as a result of Brexit, but is vying with other European cities including the French capital.
Paris, Mr Sapin said, already has four systemically important banks, the city is number two in Europe for insurance and is home to the continent's second biggest stock market, Euronext.
"The city definitely has the potential to become the Eurozone's number one financial hub," Mr Sapin said. "France has also become a more attractive place to do business again, for reasons that go well beyond Brexit. Our country's image has changed in the last five years. Foreign investment is at its highest level for a decade, as the government has taken active measures to make France more competitive and boost its appeal."
Asked if he supported the European Commission's decision that Apple must pay back taxes to Ireland, the minister said France has no claim to the money.
Also asked if he supported Eurogroup chair Jeroen Dijsselbloem, after recent comments the latter made about southern European countries, Mr Sapin said he had made his views known privately, and that the matter for him was now closed. Mr Dijsselbloem, who is also the Dutch finance minister, has rejected calls for his resignation, but said he regretted comments suggesting southern European countries had squandered their money on "booze and women".
Mr Sapin will meet with Finance Minister Michael Noonan today.
The EU's soul-searching exercise on its future direction promises nothing revolutionary. Afraid of rocking the boat ahead of elections in France and Germany, and with Brexit talks looming, EU leaders kept things low-key for the 60th anniversary of the bloc's founding treaty.