BORIS Johnson has been rebuked after falsely suggesting that Covid-19 could be in the UK water supply.

A Number 10 spokesman was forced to correct the Prime Minister after he made the remarks in Parliament while outlining new measures to tackle the pandemic.

Johnson suggested that the disease could be tracked in the water system, aiding local responses to infection "flare-ups".

He told MPs: "The intention is that the covid alert system in time will be sufficiently sensitive and flexible so as to detect local flare ups, so that if for example the Covid is detected in the water supply of a certain town or whatever then steps can be taken, or in a school or whatever then steps can be taken on the spot to deal with that flare up."

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Afterwards, the Prime Minister's spokesman claimed he was referring to sewage water rather than the water that comes out of the tap.

“That specifically is a reference to sewage or waste water as it’s more politely described,” the spokesman said.

"Some studies have been carried out overseas on this and I think it is something we are looking at as a possible way of seeing if you could track the rate of infections locally.”

The comments were denounced by a trade association which represents major water companies.

Water UK tweeted: “Earlier today, PM Boris Johnson mistakenly referred to COVID-19 being in the #water supply.

“It’s not, and No. 10 has now issued a correction. Your tap water remains perfectly safe.”

Former Labour MP Anna Turley posted on social media: "The man is a dangerous liability."

Another Twitter user asked: "Could he be more inept?"