BORIS Johnson has refused to say whether he would back Brexit or the Union if forced to make the choice.

The Tory leadership frontrunner has made much of his pro-UK credentials during the contest to succeed Theresa May. Yet, when repeatedly asked for which principle he would put first, he has failed to supply a comment.

The National contacted Johnson’s Scottish campaign director Ross Thomson with the question on Thursday last week. After failing to get a reply, we put the question to Johnson again yesterday – at the time of writing, we are still to receive a response.

During a visit to the north-east of Scotland last week, Johnson’s rival Jeremy Hunt replied “the Union every time” when the same question was put to him.

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The answer was said to have informed Ruth Davidson’s decision to endorse Hunt, and subsequently 18 other of the 31 Scottish Conservative MSPs.

Johnson’s failure to answer the question comes ahead of a leadership hustings in Perth on Friday when the question may be put again.

Hunt appeared to soften his position in an interview on Sunday on BBC’s Andrew Marr programme. Challenged that contemplating a no-deal Brexit contradicted his pledge to prioritise the Union, the Foreign Secretary said: “It’s not a question of choosing one or the other.”

He then reiterated his pledge before adding he agreed with Tory members that “we want both”.

Hunt also insisted he could protect the Union in a no-deal Brexit, despite admitting that Nicola Sturgeon would use it to push for independence.

Hunt’s campaign also issued a direct challenge to Johnson to “stop dodging questions” over whether he would protect the Barnett formula, which allocates higher public spending in Scotland.

However, sources in Johnson’s campaign said there would be no change to the formula despite previous statements that he would want it reformed. His pledge to pursue a no-deal Brexit in the face of strong opposition in Scotland represents another headache for Davidson (pictured below).

It came as Johnson said on Sunday he would take on a new title of “minister for the Union” if he enters No 10.

Senior Scottish Conservatives have expressed concern that a no-deal Brexit will increase support for Scottish independence. A Panelbase poll for the Sunday Times found support for a Yes vote has risen to 49% and would rise to 53% if Johnson becomes PM.

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Another, more recent poll suggested that 51% of Scots back an early second independence referendum.