Boris Johnson has been accused of breaching the ministerial code after jetting to a by-election campaign earlier this year.
The Tory Prime Minister flew on April 1 five days after the start of the hotly contested Hartlepool vote campaign got underway.
After landing in Teeside International Airport he was taken by motorcade to a B&Q story in Middlesborough on government business to promote a rise in the minimum wage.
However, following the visit he met with Tory Hartlepool candidate Jill Mortimer for a tour of local company Hart Biologicals.
Mortimer, who went on to win the seat, and Johnson then went door-knocking, leafleting and chatted to voters in the constituency.
According to electoral rules government money should not be used for party political work.
Any cash spend by a party has to be declared to the returning officer.
Now, a document published by Business Insider suggests the Tories declared it spent nothing on transport.
In response the Conservatives claimed the cash was accounted for under a different heading.
The SNP wants “serious questions” asked about the “cronyism” surrounding Boris Johnson ‘s government.
Kirsten Oswald, the SNP ‘s Westminster Depute Leader, said: “The stench of cronyism and sleaze surrounding this Tory government grows stronger with each day that passes.
“Boris Johnson will try his best to sweep this under the carpet as usual, but serious questions must be asked over whether or not he and his ministerial colleagues have, yet again, broken the Ministerial Code.
“Seeing as Douglas Ross was so keen to ensure others upheld the Ministerial Code in the past, he will no doubt speak out on this without delay.
“It is clear that the Westminster system is rotten to the core and broken beyond repair. Scotland can, and must, shake off the Westminster system in order to build a fairer and more democratic future as an independent nation.”
According to Electoral Commission guidance it underlines that transport costs includes “party members, including staff members (…) around the electoral area, or to and from the electoral area (…) where they are undertaking campaigning on behalf of the candidate.”
Parties can spend up to £100,000 in by-election campaigns.
During the Hartlepool by-election the Tories spent £86,991.
The Ministerial Code states that ministers “must not use government resources for Party political purposes.” It also says that “where a visit is a mix of political and official engagements, it is important that the department and the Party each meet a proper proportion of the actual cost”.
A Conservative Party spokesperson told the Mirror that “tours and associated costs” were all “declared in accordance with the rules” and were included 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 spokesman said.
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