Workplace stress is becoming an increasing problem affecting the performance and productivity of staff, claims income protection insurer Unum.

Its survey of more than 1,000 workers reveals that two-thirds feel stressed or under pressure at work.

Significantly, 73% of respondents said their performance at work has suffered because of the stress they experience. More than 83% said their working environment has become more stressful over the past five years.

Academic professor Cary Cooper said employers should be concerned at the results.

He said: “The Unum survey confirms that a combination of long working hours and an autocratic management style are key sources of stress in the workplace.”

He added that employers needed to move away from long working hours, claiming they are counter-productive, leading to higher levels of illness.

Respondents to the survey said that shorter working days and a more understanding boss would most help to tackle the problem.

Eugene McCormack, Unum's marketing director, said: “This survey should be seen as a wake-up call for the UK's business community.

“The strength of many businesses is built on the comitment of their people, yet they appear to be allowing the working environment to become increasingly stressful – and it could cost them dearly.”