HSBC has been criticised for an advertising campaign that claims the UK "is not an island".
Thousands of people have reacted on social media, with some claiming the adverts are anti-Brexit.
However, HSBC told the BBC the campaign was "not about Brexit".
The agency behind the campaign, JWT, said the work was in response to the current "atmosphere" and to remind people that we are all global citizens "whatever the political climate".
One social media user questioned whether the HSBC risked "alienating a large number of potential customers" with the campaign.
From a creative perspective, I like the copy in the new HSBC ad. But it fails to give a single, solid reason to bank with them. And - in these divided times - does it risk alienating a large number of potential customers? #business #marketing #leadgene…https://t.co/L9By5UAsCS— Martin Sayers (@MSthecopywriter) January 7, 2019
Bob Seely, MP for the Isle of Wight, took up the subject on Twitter, asking whether Brexit could mean "higher standards for banking".
The mixed response has included praise of the adverts, with some calling it "brave".
An HSBC UK spokesperson said: "With the 'We are not an island' poster we are reinforcing our strong belief that the things that make us quintessentially British are the things that make us inescapably international."
The advertising industry magazine Campaign has published images of the design of regional variations of the design.
Versions have appeared in Leeds, Birmingham, Manchester and London.
They feature references to the Otley Run in Leeds, and the formation of Oasis in Manchester.
The campaign, which has the tagline "together we thrive", includes a TV advert featuring British comedian Richard Ayoade.
It comes as HSBC is implementing changes to the way it operates in the UK.
In August, the bank revealed it had shifted ownership of its Polish and Irish subsidiaries from London to France, ahead of Britain's exit from the EU.
It plans to do the same for seven additional European units.
HSBC and other long-established lenders are facing heightened competition for customers from new rivals.
Digital banks such as Monzo offer a primarily app-based service, with appeal to a younger generation of account holders.
In a bid to remain competitive, HSBC has been offering an upfront payment for switching to its current account.
HSBC, which derives from the company's earlier name of Hongkong and Shanghai Banking Corporation, was founded in 1865 in British-ruled Hong Kong.
In 1992, it agreed to move its head office to London, after acquiring Midland Bank.
It has considered moving its HQ back to Hong Kong, but in 2016 committed to staying in London's Canary Wharf.