Thousands of alleged tax debtors in Buenos Aires face having safety deposit boxes raided by provincial authorities unless they settle their tax bills.
Some analysts question whether the proposed move breaks banking secrecy laws
Santiago Montoya, the province's treasury undersecretary, has asked banks to inform the authorities if the 35,000 alleged debtors have boxes.
Mr Montoya told the BBC that his department was seeking legal permission to seize any boxes uncovered.
He said those targeted owed more than $300m (£171m).
Buenos Aires, Argentina's richest province, has 2.5 million registered taxpayers, most of whom have regularised their tax situation.
But, said Mr Montoya, this group of 35,000 tax debtors owned more than 300,000 properties, more than 20,000 cars, about 18,000 commercial firms and more than 100 boats.
"We are going to use all the legal tools at our disposal to force them to pay," he told the BBC.
He added that those targeted had a long history of non-payment of taxes, with some having received more than a dozen legal warnings to pay their debts.
THE 35,000 ALLEGED TAX DEBTORS OWN
More than 300,000 properties
More than 20,000 cars
About 18,000 commercial firms
More than 100 boats
Source: Buenos Aires government
Mr Montoya said some companies had systematically evaded taxes.
One method, he said, was for a company owing taxes to arrange a takeover by another company that was sometimes foreign but ultimately controlled by the same owners.
The "new" owners would then argue they were creditors and the first company's tax bill would go unpaid.
Published on the internet
Some analysts have said any seizure of safety deposit boxes on grounds of non-payment of taxes could break laws on private property and banking secrecy.
And boxes were likely to contain not just cash or other valuables but personal possessions of no monetary value, they said.
Mr Montoya said the proposed move was in the spirit of existing legislation. He said boxes could be seized if there was legal authorisation and that banking secrecy laws would not apply in this case.
He said that after the banks supplied him with the information he wanted, he would ask judicial authorities to seize the boxes of those taxpayers who were under a legal process.
A list of the first 2,900 targeted has been published on the internet. Mr Montoya said the complete list would be published by February 2005.