Conservative MP Alicia Kearns has raised concerns over whether Jonathan Powell, the national security adviser, can remain in his post following his wife’s references to Palestine Action on social media.

The shadow home affairs minister has written to the PM asking if Powell’s position is still tenable, despite the Metropolitan Police concluding no action was necessary over his wife’s, Sarah Helm, comments.

A No 10 spokeswoman told the BBC: “These views are held by an individual who does not represent the government in any capacity.”

Posting on X last week, Helm wrote: “God help us authors who support Palestine and Palestine Action,” responding to a discussion about the author Sally Rooney.

The Normal People writer announced last week that her books will not be supplied to UK booksellers after she announced she would use her royalties to support Palestine Action.

The Met investigation into Helm’s post found “it did not meet the criminal threshold” and the matter was dropped on Saturday.

But Kearns has written to Andy Burnham about the handling of sensitive national security information, asking whether the government has investigated the posts and whether he retains full confidence in his adviser.

She told the BBC: “We cannot have the NSA’s [national security adviser’s] wife tweeting about what decisions her husband has or hasn’t made.”

On Monday, Helm responded to a question on X about whether her husband had been involved in the decision to ban Palestine Action with the reply “nope”.

Palestine Action was proscribed as a terror organisation last year, making it a a criminal offence punishable by up to 14 years imprisonment to belong to or support the group.

An appeal against the proscription of Palestine Action is due to be heard by the Supreme Court next month, external, in a battle that has now gone on for more than year.

The Labour Against Antisemitism group also wrote to the prime minister, calling for Powell to either resign or be sacked.

The organisation pointed to Helm’s social media posts, including one from 2018 when she wrote: “Palestinians have never had their voice heard in British corridors of power. They have no equivalent of the Jewish lobby here.

“No access to ministers, still less prime ministers.”

The letter said Helm discussed her husband’s work publicly and cited a 2016 article she wrote for the Guardian, external in which she revealed details of a conversation she had overheard between George Bush and Tony Blair, when her husband had been the No 10 chief of staff.

The group said Helm would have been included in the vetting process when Powell took on the NSA role.

“Either Jonathan Powell lacks full clearance, vetting missed this, or saw it. Each is indefensible,” the letter said.

“You promised zero tolerance on antisemitism. Mr Powell’s position is untenable and his wife raises security concerns. He must resign or be sacked.”

A Downing Street spokesman said: “Jonathan Powell is one of the finest diplomats of our generation. His experience speaks for itself.

“I am not going to get into people’s private lives… the spouses of public officials are entitled to hold and express their own views.”

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