Steve Barclay has been forced to apologise after concerns were raised that he "abused" his position as Environment Secretary.
The top Tory admitted he should have formally recused himself "sooner" from a decision about a waste incinerator being built in his constituency due to a conflict of interest. Mr Barclay has come under fire after officials escalated the matter to the Cabinet Office's ethics unit.
Mr Barclay has long campaigned against German energy company MVV Environment's proposal to build a waste incinerator in Wisbech, in his North East Cambridgeshire constituency. Campaigners have object to the smell, air pollution and its appearance.
But he is not allowed to use his role as Environment Secretary to influence Government decisions if there is a conflict of interest, such as the views of his constituents.
Asked about the row at the Commons' Environment Committee, Mr Barclay said: “Firstly all ministers need to balance their constituency role and their ministerial role and I wanted to take this opportunity to apologise to the committee for not formally recusing myself sooner and updating the register of interests regarding what was well known in public but should have been updated on the actual record regarding my opposition to the incinerator.
"To reassure the committee, I’ve been clear throughout that I need to step back from any decision as Secretary of State, which is why I flagged my constituency interest and I said the policy needed to be delegated to another minister, recognising the importance of the ministerial code, in terms of conflicts of interest and also the perception of any conflicts of interest.”
He said he wasn’t aware until later that he required a “formal recusal” as he thought he had resolved it by delegating it to another minister.
But Shadow Environment Secretary Steve Reed said the public "deserve answers" about the full extent of his involvement. “It is unlawful for senior ministers to abuse their position to prop up their constituency vote. Yet there are now serious concerns this is exactly what Steve Barclay has done," he said.
“The British public deserve answers. Who did Barclay try to persuade, when, and which other ministers were involved. The Conservatives are only interested in saving their own skins. Labour will act to save our rivers, countryside, and farming communities.”
Labour MP Barry Gardiner asked top official Tamara Finkelstein to confirm to him after the session whether there was any record of Mr Barclay discussing the matter with the Environment Agency (EA) or any junior ministers, and for the exact date he recused himself.
Mr Barclay himself then added: “I’ve never made representations as Secretary of State to the EA in terms of the incinerator in Wisbech.”
The Department for Energy Security and Net Zero said the plant could go ahead last month but it also needs a permit from the EA, which is sponsored by Mr Barclay's department. The plant would burn non-recyclable waste to generate energy for local industrial use and would be one of Europe's biggest waste-to-energy incinerators.
The row over Mr Barclay's influence deepened after it emerged a top government lawyer warned a plan that would have stopped the incinerator being built for up to a year was unlawful. A legal note seen by the BBC raised "serious concerns of perceived bias" over the issue. It warned the decision could be challenged by the courts, who might say it had been taken "on grounds of political advantage, rather than on legitimate policy grounds".