In a leaked audio recording revealed Tuesday, UK Conservative Liz Truss, the favorite to become prime minister next month, bashed her fellow Britons and said they lacked "talent and application" and needed to work more.

Truss stated that the workers' "mindset and attitude" were partly to blame for the UK's comparatively low productivity in the two-minute audio clip, which dated from her time as a senior minister in the finance ministry between 2017 and 2019.

"It's working culture basically," she said in the recording, obtained by The Guardian newspaper, adding that British workers needed "more graft".

"If you go to China it's quite different, I can assure you. There's a fundamental issue of British working culture... I don't think people are that keen to change."

The humiliating disclosure comes as Truss leads competitor Rishi Sunak in multiple surveys in the contest to succeed Boris Johnson as Prime Minister when he steps down early next month.

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The nearly 200,000-strong members of the party have already begun voting for their future leader, who will eventually become Prime Minister.

The winner of the summer-long competition will be announced on September 5, with the new leader taking over the following day.

The two main contenders took part in a hustings event in Scotland on Tuesday evening, after waging a heated struggle in recent weeks that included numerous aggressive briefings and counter-briefings by their teams.

The incendiary remarks by Truss echo controversial arguments made in a 2012 book she co-authored, "Britannia Unchained", in which British workers were described as among the "worst idlers in the world."

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When asked about it during a leadership debate last month, Truss distanced herself from the disputed report, stating it was written by co-author and Sunak supporter Dominic Raab, who is now the Justice Minister.

Raab later stated that the book's authors, who included many other top Conservative ministers, had accepted to "share responsibility" for its contents.

'More graft' 

In the leaked recording, Truss – who supported remaining in the European Union during the acrimonious 2016 referendum before switching to Brexit – appears to indicate that the EU and migration are unfairly vilified.

"We say it's all Europe that's causing all these problems. It's all, 'it's migrants that's causing problems'.  "But actually what needs to happen is, you know, a bit more graft," she said, with a laugh, before adding, "It's not a popular message."

A Truss campaign source branded the leaked comments "half-a-decade-old" and lacking "context" while acknowledging that Britain does "need to boost productivity."

"As prime minister, Liz will deliver an economy that is high wage, high growth, and low tax," the source added.

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Meanwhile, at the start of the hustings event in Perth, Scotland, both candidates restated their opposition to another referendum on Scottish independence, after Scots narrowly decided to remain in the UK in 2014.

The SNP, led by First Minister Nicola Sturgeon, claims that Brexit has changed the constitutional discussion and proposes a second referendum in October 2023. Sunak said he couldn't "imagine the circumstances" in which he would grant another referendum.

The Supreme Court in London wants to hold hearings on whether that would be allowed without approval from the UK government on October 11 and 12, this year. "We're not just neighbors, we're family and I will never ever let our family be split up," Truss told the audience of Scottish Conservative party members to applause.

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