Kate Forbes has claimed a key Scottish Government recycling scheme could cause "economic carnage".
The finance secretary, who is running to replace Nicola Sturgeon as SNP leader, said she would "halt" the deposit return scheme (DRS) if she was elected.
Forbes claimed it was a "well-intentioned" idea - but warned it was causing businesses to "fear for their future" ahead of its planned launch in August.
Speaking on a visit to Cairngorm Brewery in Aviemore today, Forbes said: "Businesses like this are fearing the economic carnage it will cause if the timetable continues as is planned right now.
"Every business wants to recycle. We are speaking right now in the middle of a national park - an area committed to environmental sustainability.
"Businesses want to recycle and many already do so in imaginative ways.
"The idea of the deposit return scheme is sound - it works well in other countries - but we cannot have a scheme that is well-intentioned but fails to achieve its aims and causes economic carnage in the process".
Forbes said small producers faced unfair complexity and added costs if the plan was implemented as currently planned.
The flagship Scottish Government initiative is aimed at increasing recycling via a 20p deposit on single-use drinks bottles and cans.
Companies are required to register for the scheme by March 1 ahead of its planned launch on August 16 this year.
But there are fears the extra costs for businesses will have a "major negative impact" on Scotland's many independent breweries.
Forbes said: "One of my first acts as First Minister would be to not just halt and to pause this scheme, and to instruct an independence review, but how we give small businesses who are the foundation of the local economies, the breathing space they need."
She added: "Under my leadership, the intention is to reset the relationship with business, with small and medium-sized businesses, who are the backbone of the Scottish economy."
Under the scheme every Scottish producer will have to add a 20p to every product before it is sold anywhere in the country.
The charge is passed on to retailers and in turn to customers who can claim cash back for every returned bottle or can.
UK Hospitality Scotland has urged SNP leadership candidates to put the "flawed" scheme on the back burner amid concern over the impact it will have on trading.
But businesses have until midnight on Tuesday to sign up for the controversial scheme and industry figures have warned it could impose potentially fatal costs on their business.
Lorna Slater, the Scottish Government minister who is pushing the scheme, said at the weekend that small drinks producers may be given a one-year exemption.
UK Hospitality Scotland executive director Leon Thompson said: "The flawed model, complexity and burdens of the scheme will put unnecessary pressure on both businesses and consumers, who are all struggling with the cost-of-living crisis.
"These cast-iron facts, alongside concerns around how it could impact trading with the rest of the UK, necessitate an immediate halt to the scheme’s introduction and I am calling on all leadership candidates to commit to pausing and then ordering a full review of this now discredited scheme.
"With all nations in the UK planning to introduce a deposit return scheme, we need to see a UK-wide scheme that works for businesses and consumers, as well as all our sustainability and net-zero goals."
To sign up to the Daily Record Politics newsletter, click here.
