Nicola Sturgeon has accused David Cameron of making "overblown claims" against Brexit in a "fear-based campaign" that could end up backfiring.
Scotland's first minister, speaking in London to launch a "positive case" for staying in the EU alongside Plaid Cymru leader Leanne Wood and Green MP Caroline Lucas, said the prime minister's persistent warnings against voting Leave risk "insulting people's intelligence".
Sturgeon's comments came on Monday, hours after Cameron and chancellor George Osborne released new Treasury analysis that predicted as many as 820,000 jobs could be lost if voters choose to leave the EU in 23 June's referendum.
"I think in Scotland, certainly, we've got lots of experience of Treasury reports during referendum campaigns," Sturgeon told the BBC, referring to similar warnings against Scottish independence in 2014's referendum.
"People have got the savvy to see through some of the overblown claims. Of course, there would be an economic impact short-, medium-, and long-term if there was a vote to leave the European Union, but I'm much more interested in the reasons to stay in the European Union, the positive reasons."
Sturgeon went on to list the protection of employment rights, the investment and jobs that come with being part of the single European market, and health and safety protections as positive reasons to stay in the EU.
Pressed on whether Cameron's tactics could actually damage the Remain case, Sturgeon said: "You only have to look at the Scottish referendum to know that that kind of fear-based campaigning, that starts to insult people's intelligence, can have a negative effect.
"I don't have complete control over how George Osborne chooses to campaign. I hope he and others choose to campaign positively in the weeks to come."
Sturgeon's comments have already been seized upon by the Scottish Vote Leave campaign, who said they "share her faith" that voters will not be swayed by warnings from Cameron and Osborne.
"Scottish Vote Leave welcomes Nicola's comments," said Scottish Vote Leave director and former Labour MP Tom Harris. "David Cameron calls Remain a 'positive campaign' but we in Scotland know it's just Project Fear. Even supporters of a Remain vote are saying it.
"As Nicola mentioned, the Treasury claims are overblown and are an attempt to scare the voters. Yet I, like Nicola, have complete faith that the voters will see through this blatant attempt at scaremongering.
"It's time for David Cameron to listen to supporters on his own side and stop insulting the electorate's intelligence with false reports. If Nicola would like to join us in fighting to secure more powers for the Scottish parliament our door is always open."