British Gas has announced it will cut 500 jobs.

The Big Six supplier said it is part of its ongoing strategic review “in order to be competitive in a fast-changing energy market”.

Employees working in the loft and cavity wall insulation business are expected to be affected.

It follows 6,000 job cuts announced by owner Centrica last summer.

Mark Hodges, Chief Executive, Energy Supply & Services, UK and Ireland, said: “We are focused on improving the efficiency and effectiveness of our organisation to meet the changing needs of our customers. British Gas is well positioned to grow but we must ensure that our costs allow us to be competitive for our customers.”

GMB Union described the announcement as a “real sickener”.

National Officer Brian Strutton added: “At the end of last year we went through a reorganisation which we were told was to make that business competitive and everyone thought that was behind us but it seems while we were doing that the company was hatching secret plans to shut the whole operation down.

“Now the government will need to look at revising it’s carbon emission targets as a result of these and other job losses in the insulation sector.”

Yesterday oil giant BP said it plans to reduce 3,000 more jobs by 2017.