CEO and chief ombudsman Ms Wayman announced the decision on social networking site LinkedIn, saying that it had been an “honour and a privilege” to have led the ombudsman for seven years.

Ms Wayman said: “The service has reached a pivotal point; in 2021 we expect to receive our final PPI cases and as nations, organisations and individuals, we are contemplating a landscape shaped and forever changed by a global pandemic.

“It’s against this backdrop, that the service is embarking on the next phase of its journey and it’s time for me to do the same.”

Earlier this week, an investigation by Money Mail reported a logjam of 158,000 complaints was waiting to be cleared. According to the investigation, one in six complaints were over a year old and 11,648 date back for more than two years.

The backlog of complaints at the ombudsman has been exacerbated by the pandemic but is not a new problem.

The FOS came under fire in 2018 following a documentary by Channel 4’s Dispatches which alleged some decisions were not fair to consumers. The documentary alleged investigators at the FOS had been speeding through decisions in an attempt to meet targets that had not been feasible due to a backlog of claims. At the time the ombudsman was handling over 300,000 new claims a year.

Later the same year an independent review found that there was no institutional bias against consumers but raised concerns about the levels of knowledge of some investigators.

The FOS has seen a huge workload of PPI cases in recent years, although this is now declining, and a rise in SIPP and pensions cases.