A watchdog has called for a government rethink after discovering the NHS is set to axe the collection of key data on smoking, drinking and other health issues to cut costs.

The UK Statistics Authority said the move would “seriously undermine the UK’s ability to monitor key trends affecting public health” and appeared to be in breach of the law.

It called on health secretary Andrew Lansley to halt the move, which UKSA said was decided without consultation with users, contrary to the code of conduct on official figures.

In a letter to the Cabinet minister, UKSA chairman Sir Michael Scholar said the NHS Information Centre had decided to cut, with immediate effect, the circa £300,000 a year it contributes to the compilation of the General Lifestyle Survey by the Office of National Statistics.

He said the ONS could not make up the shortfall, after suffering cuts itself, “without damaging their own vital economic and social statistics”.

“The decision by the NHS Information Centre will, therefore, result in the immediate discontinuation of long-established national statistics on smoking, drinking, health conditions and use of heath services,” he wrote.

“The Statistics Authority is concerned that the abrupt discontinuation of a time series on topics as central to public policy as smoking prevalence and alcohol consumption will seriously undermine the UK’s ability to monitor key trends affecting public health.”

While other sources of similar data may be available, “these are likely to be inferior to those currently in use”, he said.

Sir Michael said no user consultation appeared to have taken place - in breach of the Department of Health’s statutory duty to ensure the code of conduct was respected.

Drawing Mr Lansley’s attention to what he said were the “powerful arguments for retaining these statistics”, he told him: “I urge you to reject the Information Centre’s proposal.”

The survey gathers information from around 15,000 households on a variety of topics including housing, education, income and employment as well as health.

The most recently-published set of data, from 2009, was sponsored by ONS, the Information Centre, the Department for Work and Pensions, HM Revenue & Customs and the Scottish government.

A Department of Health spokesman said: “No decisions have been taken and discussions are still ongoing with the Information Centre.

“The department will respond to Sir Michael Scholar once these have been completed.”