A cartoon of Rishi Sunak as a laughing vampire has been rejected by the UK’s biggest outdoor advertising firm, over fears it 'slanders' the Prime Minister.

The controversial image was commissioned by Alex Salmond’s pro-independence Alba party to highlight the “bright future” for the North Sea oil and gas industry, and the revenue heading to the Treasury.

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It’s an update of a famous SNP poster about Margaret Thatcher from the early 80s. Under the picture of Mr Sunak, the text reads, “No wonder he’s laughing, he’s got Scotland’s oil.”

The Herald:

The picture has already sparked some controversy. Conservative MSP Murdo Fraser suggested it could be considered racist, a claim utterly rejected by Alba.

In their email, seen by the BBC, Global say the caricature of Mr Sunak as an oil drinking vampire slandered the Tory leader.

The firm said: "The only political messages we allow to run are basic messages such as vote for us, but not when a party is slandering someone."

Alba general secretary Chris McEleny compared the row to the decision of Coutt’s Bank to “debank” Nigel Farage.

He said: "If a company accepts political advertising we are entering a potentially dangerous place if they then want to pick and choose which political messages it supports and which it wishes to censure because it doesn't agree with them.

"In a democratic society, a political message that criticises the government of the day and the way it squanders resources is completely legitimate."

"There are parallels here to banks picking and choosing who can bank with them, advertising companies would do well to remember how that saga ended up," Mr McEleny added.

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Over the weekend, when the image first appeared online, Mr Fraser tweeted: “This is where Scottish politics is in 2003 [sic], our first Asian heritage Prime Minister being depicted in this way.

“More than a little distasteful @AlbaParty.”

Tasmina Ahmed-Sheikh, Alba's chair, replied to the tweet, “Of course anyone who knows anything about Scottish politics would recognise this as an interesting update of a poster from the highly successful ‘It’s Scotland’s Oil’ campaign – originally devised about Margaret Thatcher.

“Nothing to do with colour, all to do with substance.”

No 10 has said they hope to extract as much oil and gas from the North Sea as possible. At the end of last month, Mr Sunak announced more than 100 new drilling licences, as part of the UK Government's “maxing out” policy.