The Prime Minister was visiting a Diageo distillery near Elgin as he took his general election campaign to Scotland to argue “cynical” tariffs on whisky would “vanish” if the UK left the EU.
Mr Johnson insisted Scots were promised the 2014 vote as a “once-in-a-generation thing” after being questioned on the SNP leader Ms Sturgeon’s earlier comments that he would find the case for another referendum “irresistible”.
Asked if he could give a cast-iron pledge to voters to not agree to another referendum, he said: “Absolutely, there is no case whatever, because people were promised in 2014 – absolutely clearly – that it would be a once-in-a-generation event and I see no reason why we should go back on that pledge.”
Reacting to Labour’s statement that it would not do any deals with the SNP, Mr Johnson said: “Pull the other one – it’s got bells on.
“It’s perfectly obvious that Jeremy Corbyn is going to rely on the SNP to get him into power and to do that he’s done a shady deal to have a second referendum.”
It came as Jeremy Corbyn visited Rossendale and Darwen, saying it was the 15th constituency he had visited in the campaign.
He said: “Our campaign got off to a flying start as soon as we called this election.”
Mr Corbyn said the election was the “chance of our lives” to bring a sense of unity across all “the supposed divides”.
“I’m loving this election campaign,” he said. “I hope you’re loving this election campaign and when you knock on the doors to get Alyson [Barnes] elected here that means that means that’s one more Labour MP that will be part of that majority Labour government on.”
“There’s something wonderful and therapeutic about knocking on doors in the rain.”
Meanwhile, Liberal Democrat leader Jo Swinson took her election fight to the south-west of England as she used a visit to Somerset to push the party’s environmental agenda.
Visiting an eco-friendly nursery, Ms Swinson lit a fire using wood and cotton, and toasted marshmallows.
While she was there, she insisted that she would not be “bullied” by the online abuse women receive in public life.
Ms Swinson said she received “a lot of abuse” but it is not just politicians who are targeted on social media.