Former cabinet minister and Labour Party deputy leader Lord Tom Watson has become a senior vice president at US tech firm Palantir.

Announcing his appointment on X, Lord Watson said Palantir was “the most interesting company on the planet, doing work of real consequence”.

He said the company had “challenges” and that while some criticism was “propaganda” there were “legitimate questions about large technology companies and sovereign control”.

Green MP Sian Berry said: “This is yet another example of the corrosive revolving door between politics and big business lobbying that has no place in public life.”

She added: “Palantir, with its work for ICE (Immigration and Customs Enforcement) in the US and the IDF (Israel Defense Forces), has no business at all in our NHS and public services.

“Tom Watson has been employed to lobby his friends in the Labour government.”

Palantir builds software aimed at allowing organisations to make better use of their data and holds a large number of UK government contracts including with the NHS, the Ministry of Defence and 11 police forces.

The company has attracted controversy, with some MPs calling for more scrutiny of its use of data within NHS contracts.

Palantir is currently involved in a legal battle with the Mayor of London’s office, over its decision to block the Metropolitan Police from agreeing a contract with the company.

The Mayor’s Office said it was not satisfied the deal adequately ensured value for money but also raised concern about the firm’s values.

Palantir has argued that its software has improved NHS databases in a number of areas such as waiting lists and hospital supplies, while its work with police forces has helped tackle corruption and identify women at risk of domestic violence.

Louis Mosley, head of UK and Europe at Palantir Technologies, welcomed the appointment of Lord Watson saying he brought a “deep understanding of how AI is changing the ways the state can help people in Britain, where more than one in six Palantirians are based”.

Lord Watson was a Labour MP for more than 20 years and became a senior figure in the party, serving as a minister as well as a key behind-the-scenes operator, who reportedly orchestrated efforts to remove Tony Blair as prime minister.

In 2015, he was strongly criticised for publicising unsubstantiated claims of sex abuse by the Conservative politician Leon Brittan.

Brittan died before learning that the police had dropped their investigation and that he had no case to answer.

At the time, Lord Watson said he was “sorry for the distress Leon Brittan’s family experienced” but that he felt he had a “duty” to report claims.

After leaving the House of Commons he was given a peerage and took up a position as the chair of UK Music.

In a statement, he said Palantir was “helping Britain and its allies defend themselves, helping police protect our citizens and helping NHS staff get patients treated and home sooner”.

“We have challenges. Some criticism is propaganda. Some raises legitimate questions about large technology companies and sovereign control. Both require answers.

“Part of my role will be to correct false information while working with our engineers to ensure privacy, security and respect for sovereignty are at the heart of everything we do.”

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