British Prime Minister Boris Johnson leaves 10 Downing Street to attend the final Prime Ministers Questions before summer recess on July 22, 2020 in London, England. (PHOTO / GETTY IMAGES / BLOOMBERG)

UK Prime Minister Boris Johnson will stress the value of the UK in a visit to Scotland on Thursday, seeking to head off growing support for Scottish independence.

Tension has been growing between the administrations in London and Edinburgh in recent months, over issues including the handling of the coronavirus pandemic and calls by the governing Scottish National Party to hold a fresh independence referendum.

“The last six months have shown exactly why the historic and heartfelt bond that ties the four nations of our country together is so important,” Johnson said in a 10 Downing Street statement, highlighting areas such as the coronavirus job retention program and the national testing effort that have benefited citizens in Scotland. “The sheer might of our union has been proven once again.”

Tension has been growing between the administrations in London and Edinburgh in recent months, over issues including the handling of the coronavirus pandemic and calls by the governing Scottish National Party to hold a fresh independence referendum

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A perception that the semi-autonomous administration in Edinburgh has better handled the crisis has buoyed support for Scotland splitting from the UK, with a latest survey by Panelbase showing 54 percent of voters now favor independence, compared to 51 percent last year. In 2014, Scotland voted to remain in the UK by 55 percent.

On Twitter, Sturgeon said she welcomed Johnson’s visit because it “highlights” a key argument for independence, that other politicians make decisions on Scotland’s behalf.

Ian Blackford, the leader of the Scottish National Party in Westminster, criticized Johnson ahead of his trip, saying the devolved administration in Scotland had performed better during the pandemic.

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“The days of telling Scotland that we are either too wee, too poor or too stupid really are over,” he told BBC Radio on Thursday. “What we’ve demonstrated over the past two months in the areas of devolved responsibility and of public health is that the leadership that has been shown by our First Minister is in sharp contrast with the bluster we have seen from Boris Johnson.”

Ahead of Johnson’s visit, the UK government said it would give an extra 50 million pounds (US$64 million) to support economic development in Orkney, Shetland and the Western Isles. It also said 900,000 jobs had been protected by the Treasury’s virus interventions, about 17 percent of Scotland’s total population.