Marks will become the new chief executive and permanent secretary at HMRC in the new year, when he will leave his job as permanent secretary for the Scottish government.

Harra has been at HMRC for 40 years and CEO since 2019. He extended his term by six months from the usual five-year tenure, to lead HMRC through the general election and the following months.

Marks will face a full inbox when he takes over the top job at HMRC, with ‘unacceptable’ service levels, resourcing pressures and the complex rollout of Making Tax Digital for Income Tax all priorities for the tax authority.

The last few years have been turbulent for HMRC and it has been heavily criticised for ongoing customer service failures with long waiting time on helplines and the increasing complexity of tax putting the system under pressure.