The Tory leadership frontrunner told an event in Perth on Tuesday that she would “not allow” another independence vote if she becomes prime minister on September 5. Demonstrators gathered outside the town’s concert hall as they chanted ‘Tories out’ and held ‘Scots not British’ banners as they scaled barriers in the most tense clashes to date – and the first and only one in Scotland. Politics Hub: Truss gets the loudest boos in Perth Ms Truss and Sturgeon have traded blows since succession favorite Boris Johnson said it was best to “ignore” the Scottish First Minister and her persistent calls for a new independence referendum. The SNP leader hit back, saying that in her limited dealings with Ms Truss, the Foreign Secretary seemed more interested in asking her how to get into Vogue magazine. Use Chrome browser for more accessible video player 0:37 Nicola Sturgeon is ‘attention seeking’ Inside the chamber, Ms Truss called herself a “union child” as she lived in Paisley as a young woman – and said the Scottish Government should improve its record rather than seek another vote. The Scottish Government is pushing for the decision on whether to hold a referendum to be taken out of Westminster, with the High Court to rule on the legality of holding an advisory vote next year. Mrs Truss said: “If elected Prime Minister, I will not allow another referendum on independence. “At the time of the 2014 referendum, it was agreed by the SNP that it was a once-in-a-generation referendum. “I believe that politicians keep their promises and Nicola Sturgeon should keep her promise. “What he should be doing, rather than campaigning for another referendum, is to deal with the very real issues in Scotland.” He added that the Scottish Government would have to tackle NHS delays. Ms Truss’s comments were somewhat overshadowed by questions about a leaked recording in which she said British workers needed “more graft” and lacked “the skill and application” of foreign rivals. The clip, obtained by The Guardian, was recorded five years ago but came before the strikes. Read more from Sky News’ political team: ‘No sign’ of 40 new hospitals promised by Tories at last election Starmer says his ‘radical’ energy plan is answer to cost of living crisis Use Chrome browser for more accessible video player 1:28 Sunak on tax plans and Sturgeon Meanwhile, Rishi Sunak was less emphatic in rejecting another independence referendum. The former chancellor said he accepted the union was “consensual” and that he did not think “now or any time in the near future” was the time to consider another vote. “We live in a union which, of course, is there by consent and democracy and I accept that, but I just don’t think anyone thinks that now or anytime in the near future is the right time to focus on that. ,” he said. Westminster SNP deputy leader Kirsten Oswald said the event was “depressing viewing” for people in Scotland and said the candidates were trying to “take Thatcher out of each other”. “The couple have tried repeatedly to tell us tonight what Scotland wants,” he added. “Scotland has made it clear what it does and does not want by repeatedly rejecting the Tories at the polls and repeatedly voting for pro-independence parties.”