A former director of Barclays Bank who has also worked as a financial regulator has been appointed City minister by Theresa May.

Steve Barclay, who backed the Vote Leave campaign, takes over the brief for the financial district at a time when other cities across the EU are aiming to grab business from the City after Brexit.

On Tuesday, Brussels outlined plans that could strip London of its coveted role in clearing financial assets denominated in euros amid warnings this could threaten 100,000 jobs across the UK. Big banks such as Goldman Sachs and JP Morgan have also said they would shift jobs out of London in response to Brexit.

The MP for North East Cambridgeshire, who was first elected in 2010, has the formal title of economic secretary to the Treasury and replaces Simon Kirby, who lost his seat in last week’s election and had faced criticism while in the role.

Barclay, according to his website, qualified as a solicitor before working in financial regulation and then financial crime prevention. He was director of regulatory affairs and then head of anti-money laundering and sanctions in the high street banking operations of Barclays. Before Barclays he had worked at the City regulator, the Financial Services Authority, and has previously said that attempts to clean up the financial sector from money laundering were flawed.

In 2014, Barclay said: “When there is a high-risk multimillion-pound transaction, the bank files a suspicious activity report, but 93% of the reports are never read.”

It is not yet clear what Barclay’s remit will be at the Treasury. His predecessor was sidelined in March from overseeing Brexit’s impact on financial services, when the task was handed to Lucy Neville-Rolfe, who tweeted on Tuesday that she had left the government.

But Barclay gave a clue to his approach to his new role. Responding to a tweet congratulating him on his appointment the new City minister said:

Miles Celic, the chief executive of lobby group TheCityUK, welcomed his appointment. “It is vital we have more champions of business representing our industry in parliament,” he said. “As we begin the Brexit negotiations, it will be essential for the government and industry to maintain a strong, open and constructive dialogue.

“This includes remaining focused on effective bridging and adaptation periods to allow for a smooth, orderly Brexit, mutual market access based on mutual recognition and regulatory cooperation, and the ability to access and supply the best global talent.”

Chris Cummings, the chief executive of the Investment Association, said: “As the UK enters the Brexit negotiations, it has never been more important for the City to have a minister who really understands and champions its needs.”

Barclay will be one of the ministers working in the Treasury under Philip Hammond, who is due to give the chancellor’s annual Mansion House address on Thursday. Hammond’s audience of bankers will be looking for signs of any softening of the government’s stance towards Brexit.

A replacement for Lady Neville-Rolfe as commercial secretary is yet to named, while Mel Stride has been named financial secretary and Liz Truss has been demoted from justice secretary to be chief secretary to the Treasury.