It comes after reports that the board of the bank was in early-stage talks over a sale to Brazilian bank Nu Holdings’ Nubank, which could see the lender sold for up to £10bn by Sky News.

Advent previously owned payments group Worldpay, before it listed on the London Stock Exchange. However, the sale of the homegrown bank, established in 2015, would be a setback for the City, with the London Stock Exchange viewing Monzo as a potential listing candidate.

Andrew Griffith, the shadow chancellor, said: “There should always be an international market for British companies, but the critical thing is that there’s a good homegrown outlet for them too.

“This is a test for the Treasury about whether it’s serious about making our financial services sector competitive.”

The move by Latin America’s biggest fintech would give Nubank a strategic foothold in Europe, as it seeks to expand globally. Monzo holds a banking license in the UK and in the EU. Earlier this year Nubank secured a US banking licence and was valued at around £49bn, with more than 140m customers across Latin America.

It comes after venture capital firms Iconiq and Accel staged a rebellion following the surprise departure of Monzo chief executive TS Anil. Shareholders demanded chair Gary Hoffman, who stepped down on August 16, 2026 and called for greater investor representation on its board. February saw Diana Layfield join as chief executive, which saw her close Monzo’s US operation and focus on European growth, launching in Spain and Ireland.