The BBC has apologised to Sir James Dyson for describing the inventor as a “prominent Conservative supporter” when he became embroiled in a lobbying row over leaked texts to Boris Johnson.

In messages first revealed by the BBC, the Prime Minister reportedly promised the entrepreneur he would “fix” an issue over the tax status of his employees after being directly lobbied by him.

The exchanges took place last March at the start of the pandemic when the Government was appealing to firms to supply ventilators amid fears the NHS could run out of stocks.

The broadcaster described Sir James as a “prominent Conservative supporter” in the reports, which prompted him to hit back at the claim.

Writing in The Daily Telegraph, Sir James said: “(The) characterisation of me as a prominent Conservative donor, or supporter, leveraging a position of power to extract favours from the Prime Minister, is completely untrue.”

The BBC issued an apology on its website on Wednesday to “put the record straight” on the matter, in which it said the James Dyson Foundation had in fact made a charitable gift to an event for schoolchildren.

It said: “We accept that Sir James Dyson is not a prominent Conservative supporter as was stated in some of our coverage of his text messages with the Prime Minister.

“The James Dyson Foundation made a charitable gift to support the Wiltshire Engineering Festival for school children. We accept that this does not signal affiliation to any political party and we would like to put the record straight.”

Sir James had also “raised concerns about the accuracy” of other aspects of the reports from last month, according to the broadcaster.

In the leaked messages, Mr Johnson promised Sir James he would “fix” a tax issue for Dyson staff working to develop ventilators.

Sir James wrote to the Treasury requesting that overseas staff would not have to pay additional tax if they came to the UK to work on the ventilator project.

But when he failed to receive a reply, Sir James reportedly took up the matter directly with the Prime Minister.

He said in a text that the firm was ready but that “sadly” it seemed no-one wanted them to proceed, to which Mr Johnson replied: “I will fix it tomo! We need you. It looks fantastic.”

The Prime Minister then texted him again saying: “(Chancellor) Rishi (Sunak) says it is fixed!! We need you here.”

Two weeks later, Mr Sunak told the Commons Treasury Committee that the tax status of people who came to the UK to provide specific help during the pandemic would not be affected.

However, the BBC said it “wish(ed) to make clear” in its apology that Sir James had initially contacted Downing Street in response to a direct request from the Prime Minister asking for support in making ventilators.

The broadcaster also raised that there were incurred costs of £20 million “which his company voluntarily absorbed in trying to assist in the national emergency”, and that the text messages were later forwarded to officials.

The statement added: “We are sorry that these facts were not always reflected in our coverage, and we apologise for not doing so.”