EY will be the, auditor for the financial year commencing 1 January 2017, subject to approval by shareholders at the annual general meeting to be held in May 2017. Deloitte will conduct the audit for the FTSE 250 oil and gas exploration and production company for the year ending 31 December 2016.

Deloitte were initially appointed auditors of the company in 2004 and the audit has not been put out to tender since that date, and in its 2015 annual report, Premier Oil signalled its intention to conduct an audit tender process in light of changes to the UK corporate governance code.

According to the annual report, the firm was paid $1.1m (£890,000) for audit services in 2015, plus $400,000 (£324,600) for non-audit services.

In its regulatory statement, the company said: ‘The board of Premier extends its appreciation and thanks to Deloitte LLP for their contribution over many years.’

In addition, Deloitte has announced it has resigned as auditor of Zegona, a company set up by former Virgin Media executives Eamonn O’Hare and Robert Samuelson with the objective of acquiring businesses in the European telecommunications, media and technology sector.

In its letter to Zegona’s board explaining the decision, Deloitte said the decision was ‘due to concerns over the composition of the board of directors and in that context, the adequacy and appropriateness of the audit committee’s oversight of the company’s system of internal control over financial reporting.’

The letter goes on to state: ‘In resigning, we have discussed our concerns with representatives of the company’s audit committee and board of directors and they have confirmed to us that they take our concerns seriously and that they will take the necessary steps to address these matters.’

KPMG has been chosen to take Deloitte’s place. Deloitte’s Spanish office will continue in its role as auditor of Telecable, Zegona's operating business, which was the company’s first acquisition for €640m (£552m) in August 2015.

Eamonn O'Hare, Zegona's chairman and CEO said: ‘We are pleased to welcome KPMG as our group auditor.  We have been impressed with the quality of the KPMG team and their understanding of the journey we are on, and we will be working closely with them as we continue to grow and develop our business.’

Deloitte has also been replaced as auditor of professional services firm Charles Taylor.

In a statement the company said it has agreed to appoint PwC as its statutory auditor for the year ended 31 December 2016, following a competitive tender process.

Charles Taylor paid Deloitte £642,000 in audit fees and £170,000 in fees for other services last year, according to the company’s 2015 annual report.

The company primarily provides professional services to clients across the global insurance market.