Boris Johnson is running to be prime minister on a platform of being able to "unite" the United Kingdom after Brexit.

However, he previously published a poem calling for the "extermination" of Scottish people.

The apparently satirical poem "Friendly fire" by James Michie, was published by Johnson when he was editor of the Spectator Magazine in 2004.

It suggests that Scotland should be turned into a "ghetto" followed by the genocide of the "tartan dwarves" within it.

Visit Business Insider's home page for more stories.

LONDON — Boris Johnson launched his campaign to become prime minister on Wednesday, stating that he was best-placed to "unite" the United Kingdom, following the divisions over Brexit.

However, when Johnson was editor of the Spectator magazine in 2004, he sparked outrage in one part of the UK, when he authorised the publication of an apparently satirical poem describing Scottish people as "a verminous race" who should be exterminated.

The poem, which has since been removed from the magazine's archive, was written by its then staffer James Michie.

It described Scots as "tartan dwarves" who were "polluting our stock" and suggested that the country should be turned into a "ghetto" with the inhabitants submitted for "extermination."

Reacting to the poem at the time, Maureen Fraser, director of the Commission for Racial Equality in Scotland, described it as "very offensive and the language is deeply inflammatory..."

She added: "Some of the language, such as 'comprehensive extermination' and 'polluting our stock', is completely and utterly unacceptable. It cannot be tolerated.''

It is not the only time Johnson has triggered offense with a poem. In 2016, he won an award for writing a limerick about the Turkish President Erdogan, who he referred to as a "wankerer" who has sex with goats.

He was subsequently made Foreign Secretary by Prime Minister Theresa May.

Johnson is a controversial figure in Scotland.

Recent polling has found that just one in ten Scots believe he would make a good prime minister with almost seven in ten saying he would make a bad prime minister.

He was also recently blocked from appearing at the Scottish Conservative conference, despite other leadership contenders being invited.

Last year it was revealed that a number of Scottish Conservative MP had launched a plot to prevent Johnson becoming prime minister, which was labeled "operation arse."

A senior Conservative party source told the Daily Record newspaper: "We called it that so we'd all be clear who we were talking about."

Other parts of the United Kingdom have not always taken kindly to Johnson either.

When Johnson was in the Shadow Cabinet under then Conservative leader Michael Howard, he was ordered to apologise to the citizens of Liverpool after publishing a leading article accusing the city of wallowing in "victim status" following the murder of Ken Bigley and the 1989 Hillsborough football stadium disaster.

Johnson's campaign did not respond to a request for comment.

Read 'Friendly Fire' - By James Michie

The Scotch - what a verminous race!

Canny, pushy, chippy, they're all over the place,

Battening off us with false bonhomie,

Polluting our stock, undermining our economy.

Down with sandy hair and knobbly knees!

Suppress the tartan dwarves and the Wee Frees!

Ban the kilt, the skean-dhu and the sporran

As provocatively, offensively foreign!

It's time Hadrian's Wall was refortified

To pen them in a ghetto on the other side.

I would go further. The nation

Deserves not merely isolation

But comprehensive extermination.

We must not flinch from a solution.

(I await legal prosecution.)