The United Kingdom and the European Union have made progress on a deal to give London’s dominant financial center basic access to EU markets after Brexit, two British officials said, but no agreement has yet been clinched.

The deal being discussed would be based on the EU’s existing system of financial market access known as ‘equivalence’ – a watered-down relationship that officials in Brussels have said all along is the best arrangement that Britain can expect.

The Times newspaper said a tentative deal had been reached on all aspects of a future partnership on services, as well as exchange of data and including what would amount to a concession from the EU on bending the ‘equivalence’ rules.

Officials in Brussels and London said The Times report was wrong.

“We are making progress,” a British official, who spoke on condition of anonymity, told Reuters. A second British official said that, while there was progress, nothing was finalized.

A spokesman for Prime Minister Theresa May said reports of a deal were speculation and that Britain wanted to go beyond the existing equivalence regimes.

The European Commission said a future financial services agreement would only be discussed after a Brexit divorce deal has been finalized.

Talks over a broader deal are mired in a disagreement over an Irish backstop – an insurance policy to ensure there will be no return to a hard border on the island of Ireland if a future trading relationship is not in place in time.

Many top bankers fear Brexit will slowly undermine London’s position as the world’s biggest international financial center, and a Reuters survey found that, so far, just over 600 are moving away.

Global banks have already reorganized some operations ahead of Britain’s departure from the European Union, due on March 29.

The pound jumped following The Times report, reaching $1.2905 by 1150 GMT and extending gains after the Bank of England hinted at a slightly faster pace of interest rates increases.

But BoE Governor Mark Carney also warned all bets were off if next March brought a “disruptive” EU departure.

Britain is currently home to the world’s largest number of banks and hosts the largest commercial insurance market.

About six trillion euros ($6.8 trillion) or 37 percent, of Europe’s financial assets are managed in the UK capital, almost twice the amount of its nearest rival, Paris.

In addition, London dominates Europe’s 5.2 trillion euro investment banking industry. New York is bigger, but more centered on American markets.

Brexit and the City

Since Britain voted to leave the EU in 2016, some of the world’s most powerful finance companies in London have been seeking ways to preserve the existing cross-border flow of trading.

The arrangements being discussed fall far short of that.

Currently, inside the EU, banks and insurers in Britain enjoy unfettered access to customers across the bloc in all financial activities.

Equivalence covers a more limited range of business and excludes major activities such as commercial bank lending.

Britain’s aim for financial services was “to go beyond existing EU equivalence regimes and agree a new economic and regulatory partnership,” a spokesman for May said. “This would be based on the principle of autonomy for each side over decisions regarding access to its market.”

Under the current system, Brussels can scrap an equivalence designation within 30 days in some cases – a step it has never taken – and Britain has called for a far longer notice period.

The Times reported that neither side would unilaterally deny market access without first going through independent arbitration and providing significantly longer notice.

The EU’s chief Brexit negotiator Michel Barnier denied this report, saying only the EU could grant and withdraw equivalence for some financial services on its own.

Barnier said that the equivalence regime, which the EU has been offering Britain since July, could only ever be unilateral.

Supporters of Brexit had hoped that leaving the EU would allow them to dispense with EU rules such as caps on bankers’ bonuses to turbo-charge London as a financial hub.

Britain’s Financial Conduct Authority said on Wednesday that UK and EU financial rules should stay aligned after Brexit, a basic condition for Brussels to grant equivalence.

Faced with having Europe’s biggest financial center on its doorstep, the EU has begun tightening conditions for equivalence in areas such as clearing derivatives and investment banking.

Britain on Wednesday said there was no set date for Brexit talks to finish, backtracking after Brexit minister Dominic Raab suggested terms could be finalized by Nov. 21.

($1 = 0.8793 euros) (Additional reporting by William James in London and Jan Strupczewski in Brussels; Writing by Guy Faulconbridge in London.)