PRIME Minister Boris Johnson used taxpayer funds to campaign in the Hartlepool by-election and breached the ministerial code, reports claim.

The Insider reports that a copy of the Conservative party’s spending return outlined the costs of the campaign, which the Tories ultimately won on May 6 this year.

Johnson flew by private jet from London Stansted to Teeside International Airport, near Middlesbrough, on April 1.

The flight took place five days after the regulated period for the by-election had started, and when spending in support of a candidate must be declared.

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Johnson then travelled in a motorcade from the airport to Middlesbrough where he visited a local B&Q to promote a rise in the minimum wage, which is official government business.

However, Johnson was then driven to Hartlepool and met with Conservative candidate Jill Mortimer.

The pair visited a local company, Hart Biologicals, as part of support for her campaign in the constituency.

Local media reported that afterwards, Johnson and Mortimer visited a nearby housing estate and took part in door knocking, leafleting and speaking to residents.

Later that afternoon, the Prime Minister flew back from Teeside International Airport to Stansted.

The National:

Johnson joined Mortimer to campaign in the by-election on multiple occasions

However, none of these costs were included in the spending return, and it clearly states that the candidate spent nothing on transport.

The summary of expendidatures in the by-election, published by Insider, says that £2997.21 was spent on advertising, £52,758.50 on unsolicited material to electors, £24,154.02 on agent and other staffing costs, and £7,102.04 on accommodation and administration.

The total campaign spend reached £86,991.77. There were no costs assigned to the categories Transport or Public Meetings.

According to guidance from the Electoral Commission, transport costs include transporting volunteers, party members, including staff members, and other campaigners, “around the electoral area or to and from the electoral area”.

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This includes costs for tickets for transport, including booking fees, hiring of any transport, the fuel purchased for the journey and also parking, “where they are undertaking campaigning on behalf of the candidate”.

The Ministerial Code says that ministers “must not use government resources for party political purposes” and when the visit is a mix of political and official engagements, “it is important that the department and the Party each meet a proper portion of the actual cost”.

A Conservative Party spokesperson told Insider: "Tours and associated costs [...] were all declared in accordance with the rules and feature on the return under 'Staff Costs.'"

"All candidate election expenses were included in the return made in accordance with the Representation of the People Act by the candidate's agent.”

The party, however, did not provide evidence or respond to requests for proof that the £24,000 staff costs included transportation.

The National:

Johnson has been accused of breaching the ministerial code by using taxpayer funds

Angela Rayner MP, Labour's deputy leader, called for an investigation into a breach of ministerial code by Johnson.

She said: "Yet again the Prime Minister behaves like the rules don't apply to him. Taxpayers' money should not be abused to fund the Conservative Party's election campaigns.

"The Prime Minister has clearly broken the Ministerial Code, and this time he can't play ignorant and pretend that he didn't know what was going on.

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"The contempt with which the Prime Minister treats the laws governing election expenses and the rules that are supposed to uphold standards in our public life shows that he is only ever interested in helping himself, not acting in the interests of the British people."

Rayner has also written to Lord Geidt, the PM’s independent adviser on ministerial standards, and Cabinet Secretary Simon Case, the UK’s most senior civil servant, demanding to know if the Prime Minister used public funds for party political campaigning.