LONDON (Reuters) – Britain must not get bogged down haggling over “pennies” in settling its Brexit divorce bill and focus instead on the “big pounds” that a trade deal with Europe would bring, the new Lord Mayor of London said.

Charles Bowman, the ceremonial head of the capital’s City of London financial district, urged the government to increase its financial offer to Brussels to break the deadlock in negotiations over a new trade deal.

Slow progress in the talks has unsettled many businesses and concern has been growing that Britain could crash out the world’s biggest trading bloc without an agreement.

“It’s pounds versus the pennies. If we are haggling over the pennies now, then we will miss out on the pounds in the future,” Bowman told Reuters in an interview at Mansion House, a Georgian town house opposite the Bank of England.

Many pro-Brexit campaigners say Britain should walk away from the talks without paying any money to Brussels to settle long-standing commitments in the bloc including pensions.

But Bowman said Britain had five weeks to secure a transition deal with its European Union partners or risk losing jobs as banks shift activities from London to the EU to keep serving customers there.

“Having a well articulated position as regards to transition by Christmas, we say is very important,” said Bowman in his first month in the job at the heart of the district that is home to more than 250 foreign banks and the stock exchange.

“My simple ask is that we need it now.” Bowman, the 690th Lord Mayor, said he had pressed his case with British Prime Minister Theresa May at his inaugural Mansion House dinner last week.

May has backed calls for a transition deal but Brussels insists on the UK agreeing to a Brexit bill first.

“TOO MUCH THE MASTER”

At a meeting on Monday, May’s Brexit committee – made up of some of her top ministers – said Britain would will honour commitments to the European Union.

Local media reported that she could increase the payment to 40 billion pounds ($53.22 billion), more than double the initial estimated offer of 20 billion euros.

“I‘m not saying it’s petty cash, not at all,” Bowman said.

At stake is the 71.4 billion pounds in tax the UK’s financial sector raises each year and 2.2 million jobs across Britain, he said.

The Bank of England expects 10,000 financial jobs to have left London for Frankfurt, Paris, Dublin and Luxembourg by Brexit Day as banks, insurers and asset managers press the button on contingency plans.

But London will remain “greatest” financial centre, Bowman said.

“We have got a very unique thing here, this cluster that can’t be replicated. It if could, it would already have been. People like London,” Bowman said.

He pointed out that Swiss bank Julius Baer is expanding its presence in London, but some jobs will go in any case even if there was no Brexit because machines are replacing bankers, lawyers and accountants.

An accountant by profession, Bowman said it was “quite terrifying” how machines were making professional judgements.

He said one of his objectives during his year as Lord Mayor will be to help restore public trust in a sector tarnished by the financial crisis and misconduct.

In his official CV, he says he spends his weekends digging up the poisonous weed ragwort in his garden, a skill that may help him root out public distrust.

“We have a duty and a responsibility to re-earn the trust of society that we are here to serve. Historically, reality or perception, we are too much the master.”