Hundreds of KPMG’s UK staff have been told to hand in their work mobile phones as the company steps up its cost-cutting drive.

The big four accounting firm said those affected are mainly junior administrative and back office staff, who do not work out of hours or at clients’ offices. The change will not affect people who travel a lot or need to be contacted outside working hours by their clients or team.

A KPMG UK spokesperson said: “Over the past year we have invested in a range of technologies to support our people, which enable them to work from home or the office with ease. As a result we have less need for mobile phones in certain areas of the business.”

The company explained the change in an internal memo sent to its UK staff: “To realise our growth ambition, we need to improve our profitability by building a leaner, more responsive cost base. This will help free up funds to invest in the future of the firm – to recruit and retain the best talent and invest in big, integrated solutions.

“Right now, our cost base is the most expensive of the larger KPMG member firms and the most expensive of the big four in the UK. We regularly review our ways of working to ensure they are market-competitive and affordable for the business.”

Its UK business services group, which has 3,500 staff and includes the finance, IT, marketing and legal teams, will be the first part of the business to implement the mobile phone restrictions. “We will then be sharing lessons learned with other parts of the [UK] business, especially where colleagues are largely office-based,” the memo says.

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KPMG, which will release its results in December, has come under pressure over its audit of the collapsed construction group Carillion, and was fined £5m and “severely reprimanded” in May for its audit failings at Co-op Bank.

The company also plans to cut about 200 of its 670 administrative support staff.

KPMG has pushed through a number of changes and last year angered UK staff by threatening them with £100 fines if they are late to file their time sheets, which record how long they spend on tasks. However, after complaints, it dropped a separate policy of charging staff for lost IT equipment such as computer privacy screens and laptop locks.