BRITAIN'S biggest water supplier has been criticised for failing to step up its performance.

Westminster Council will extend an "improvement notice'' served on Thames Water for another three months.

It says the utilities company, which covers the Swindon area, failed to carry out measures set out when the notice was first served three months ago.

Thames Water could face legal action if it does not get its act together this summer, Westminster Council said.

It first served the improvement notice because it found Thames Water had failed to provide a basic minimum standard of service in Central London.

Its criticisms relate to the company's approach to road repairs and site maintenance.