Huntsworth and Chime Communications, two of the leading UK marcoms groups, have both warned the market about their outlook as key clients have cut multimillion pound comms programmes.
Huntsworth saw a third wiped off its value in the past week after its interim statement on 18 November revealed the cancellation of more than £4m of project fees.
Huntsworth CEO Lord Chadlington said the agency started to feel a change in sentiment in October, and to really feel the impact in November.
'The whole situation has changed significantly over the past few weeks,' said Chadlington, pointing to consumer durables, electronics and healthcare as markets facing particularly tough conditions.
Chadlington suggested that clients were reluctant to pay for any additional support over their retainers and were expecting an even higher level of over-servicing.
On 8 November, Chime announced that it was being forced to cut staff and property costs after losing lucrative work with the US government.
Chime chairman Lord Bell said: 'This has affected one of our public relations businesses. As a consequence, we have moved quickly to reduce costs, mainly people and property, which has resulted in one-off restructuring costs in 2011.'