WPP-owned Finsbury, which handled the M&S corporate and City account for the last four years, will be the last agency to do such work with the retailer, a spokeswoman told PRWeek.
"We are moving to a new way of working from the beginning of April and will no longer be working with a full-service city PR agency," said the spokeswoman, who confirmed that much of Finsbury's duties would now be handled by the company's in-house PR team.
"We will bolster our roster of independent external advisors to support the team," the spokeswoman added, though declined to give further details.
A spokeswoman for Finsbury echoed the retailer's comments, but declined to comment further.
Following an RFP for a new PR brief, Grayling, and its consumer and tech division Atomic, won the business.
M&S also continues to work with WH PR in the Republic of Ireland and ASG PR in Northern Ireland, the company's spokeswoman said.
In November, M&S announced it would close 30 stores in the UK and convert 45 more into food-only shops, while also shutting 53 outlets internationally, amid falling profits. The plan is expected to cost £150m over three years.
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