Russian oligarchs are estimated to hold "at least $1 trillion in wealth abroad, often concealed in offshore companies whose true ownership is hard to determine," the economists said in a letter to the G20.
Leading economists has urged G20 leaders to draw up a world asset register for tracking tax evaders that could pressure Russia over its attacks on Ukraine by exposing oligarchs' hidden wealth.
Bestselling economists Joseph Stiglitz of the United States and Thomas Piketty of France among others made the call in an open letter published in The Guardian on Tuesday ahead of Wednesday's G20 finance meeting.
Building on progress in financial information-sharing over recent years, "it's time for a global asset register to target hidden wealth," said the letter.
It was signed by members of the Independent Commission for the Reform of International Corporate Taxation, a think tank.
Western powers have unrolled a series of tough sanctions against Russian President Vladimir Putin and his allies since he launched his attacks on Ukraine in February.
Those targeted include the billionaire owner of Chelsea Football Club, Roman Abramovich.
Global asset registry
Russian oligarchs are estimated to hold "at least $1 trillion in wealth abroad, often concealed in offshore companies whose true ownership is hard to determine", the letter said.
"On this wall of opacity, the efforts of the countries that want to sanction these are now stumbling," it added.
With populations suffering from the impact of the Covid-19 pandemic, "Russia's invasion of Ukraine has aggravated this already-worrisome context," with rising prices and insecurity, it added.
"We now have a unique opportunity to make progress on the implementation of a global asset registry" to cut through the web of front-companies and link all kinds of assets to their true owners.