The House of Lords has blocked the government’s attempts to relax rules around the pollution of waterways.

In a fiery debate on the proposed amendment to the Energy Bill, former Climate Change Committee chair Lord Deben labelled the move as “entirely unconservative” and added that it was “one of the worst pieces of legislation” he has ever seen.

The proposed amendment on scrapping nutrient neutrality measures was introduced by Levelling Up secretary Michael Gove last month. He claimed it would free up developers to build thousands of homes.

Lord Deben, however, described this stance as a “canard”: “The housebuilders are not building the houses they have already got planning permission for in areas which are not in any way affected by this. We know that perfectly well. It is a canard, if I may use a foreign word, to suggest that this will have any effect on the number of houses,” Lord Deben said.

“The number of houses in this country is not reaching 300,000 because the housebuilders have bought the land at a price which means that they can sell only at a level which is too elevated for the present time, with mortgages as they are. Let us not kid ourselves that, by voting against this, we will in some way reduce the number of houses, because we will not.”

Lord Deben went on to liken the government’s amendment to “the kind of attitude that we see in the Republican Party in the United States, the people who do not believe in climate change, the anti-vaxxers, who say ‘don’t look at the facts’.”

He added: “This is one of the worst pieces of legislation I have ever seen, and I have been around a long time. It is entirely unconservative. If all this was so obvious so long ago, why was it not included in the Bill in the first place, or in some other Bill?”

Following the debate, the amendment was voted down by the House of Lords with 203 votes against it and 156 votes in favour.

The Liberal Democrats’ Lords spokesperson Baroness Pinnock called the vote “a great victory”. She added: “The Conservatives have continually promised not to roll back our environment rules, it is deeply shocking that they can’t be trusted to keep their word.”

Angela Rayner, deputy leader of the Labour party, said the “flawed plan” had been “humiliatingly rejected” by the upper house of Parliament.

Posting on X – previously known as Twitter – the Conservative Party said: “Starmer and Labour just voted to block 100,000 homes. Why? Short-term politics over the needs of British families.”

Lord Deben will be speaking at Utility Week Forum which takes place in London on 4-5 October. For more information, click here.