Sky News has learnt that Mr Haythornthwaite, who currently chairs Ocado and the AA, is expected to be appointed as Sir Howard Davies's successor in the coming days.

City sources said that an announcement could come as early as Wednesday following the disclosure of his prospective appointment.

Mr Haythornthwaite is among Britain's most experienced businesspeople, having led a string of companies, including MasterCard International.

A friend of his said: "Rick is passionate about Britain and believes NatWest is an important company for the country."

NatWest, which remains nearly 40%-owned by the taxpayer, has endured a torrid few weeks over the closure of Mr Farage's Coutts accounts.

The then chief executive of NatWest, Dame Alison Rose, briefed a BBC journalist that the accounts had been shut for commercial reasons, prompting the publication of an inaccurate story.

It subsequently emerged that the bank had taken Mr Farage's reputation and political views into account, sparking one of the biggest rows to engulf the British banking sector in years.

Sir Howard initially sought to support Dame Alison continuing in her role but within hours was forced to backtrack after the chancellor, Jeremy Hunt, signalled that he wanted her removed.

The chairman's approach to the row stoked Mr Farage's anger at his treatment by the taxpayer-backed lender.

A number of reviews are now underway into the scandal, including two commissioned by the bank itself.

Separately, the Financial Conduct Authority is reviewing the industry's handling of politically exposed persons (PEPs), having this week unveiled the terms of reference for its inquiry.

"These rules follow international standards and are designed to keep the financial system clean, free from corruption and guard against financial crime," Sarah Pritchard, the FCA's executive director for markets, said.

"It's important that they are implemented proportionately and don't create unnecessary barriers for public servants and their families."

At the top of Mr Haythornthwaite's in-tray will be the identification of a permanent successor to Dame Alison.

Paul Thwaite, one of the bank's top executives, was elevated to replace her on an interim basis, and could be a contender for the job on a permanent basis.

While his executive career was spent as an industrialist rather than a banker, Mr Haythornthwaite is likely to have been regarded by the government and regulators as a safe pair of hands.

During his time at MasterCard, he oversaw the acquisition of VocaLink, a critical part of Britain's payments infrastructure, while he recently oversaw a review of armed forces incentivisation on behalf of the Ministry of Defence.

Sir Howard had always planned to step down before the bank's annual meeting in 2024, and it is not thought that his departure will be accelerated significantly.

A NatWest spokeswoman declined to comment.