A government minister employed a PR and lobbying firm to investigate journalists' sources before he entered Parliament.

Cabinet office minister Josh Simons was chief executive of the pro-Starmer think-tank Labour Together and in 2023 commissioned APCO Worldwide to try and identify how reporters had uncovered information about the group's funding.

In a contract for the work seen by the BBC, APCO Worldwide confirmed it would "investigate the sourcing, funding and origins of a Sunday Times article about Labour Together" as well as upcoming works by two political authors.

The allegations, first reported by investigative website Democracy for Sale, centre on how Labour Together responded to media reports about the think tank's failure to declare more than £700,000 in donations between 2017 and 2020.

Labour Together was fined £14,250 by the Electoral Commission in September 2021 over late reporting of donations.

Josh Simons said it was "nonsense" to claim he wanted to investigate journalists and he had asked APCO Worldwide to "look into a suspected illegal hack, which had nothing to do with UK journalists at Sunday Times, Guardian or any other brilliant UK newspaper".

"APCO's investigation never fully got to the bottom of this," he wrote on X.

"Those who know me know I think the work of journalists is vital to our democracy."

Labour Together and ACPO Worldwide have not responded to requests for comment.

A government source said: "We are looking into the claims".

The think tank is alleged to have hired journalist-turned-lobbyist Tom Harper from APCO Worldwide to investigate reporting by The Sunday Times and other outlets to identify their sources. Harper has not responded to a request for comment.

In the leaked contract, APCO Worldwide said it intended to "establish who and what are behind the coordinated attacks on Labour Together".

The firm said it would use open source, human intelligence and digital forensics work and its approach should "provide a body of evidence that could be packaged up for use in the media in order to create narratives that would proactively undermine any future attacks on Labour Together".

Before Simons led Labour Together, it was run by Morgan McSweeney who is now Keir Starmer's chief of staff.

The BBC has reached out to Morgan McSweeney for comment. A source close to McSweeney pointed out he was not running Labour Together at the time APCO's investigation was commissioned.

Cabinet office minister used PR firm to investigate journalists' sources