BORIS Johnson lied to the House of Commons over Scotland's tax rate, an SNP MP claims.

Facing parliament during his second time in charge during Prime Minister's Questions, Johnson said Scottish "separatists" were focussed on "smashing up" the union as a distraction from the "appalling" situation in Scotland, including the "highest taxes anywhere in Europe".

But most of Scotland's taxpayers face lower rates than those levied in England.

READ MORE: Boris Johnson wrong on claims Scots taxes are Europe's highest

Addressing Johnson's claim, Perth and North Perthshire MP Pete Wishart said: "This bizarre claim by Boris Johnson is nothing short of a lie.

"Most taxpayers in Scotland pay less than if they lived in England - never mind the higher rates faced elsewhere in Europe.

"No wonder support for the Tories is plummeting right across Scotland."

A poll published in The Times this morning suggests the Tories will lose 10 of their 13 Scottish seats if a general election is called now, with the SNP to win in 51 constituencies.

That success would put them five away from their unprecedented 2015 result.

During PMQs, Johnson said: "The separatists in Scotland drone on and on about breaking up, about smashing, the oldest and most successful political union.

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"There's a reason why they go on about it and that is to detract from their appalling domestic record. They are a total shambles - look at them.

"They have the higest taxes anywhere in Europe."

In Belgium, middle earners on a £28,000 salary are taxed at 49%.

The level for France is 48% for both Italy and Germany is 47%. The Spanish figure is 40% and Denmark's is 38%.

For the UK - according to calculations by the Institute for Fiscal Studies using data from the Office for National Statistics and Euromod - this number is 28%.

Scotland has set its intermediate rate of income tax - for those on £24,945-£43,430 - at 21%.