Leaked financial documents published by major news organisations allegedly tie world leaders to secret stores of wealth, including King Abdullah of Jordan and associates of Russian President Vladimir Putin.
The dump of more than 11.9 million records, amounting to about 2.94 terabytes of data, came five years after the leak known as the "Panama Papers" exposed how money was hidden by the wealthy in ways that law enforcement agencies could not detect.
The new cache of documents has been dubbed the Pandora Papers.
The International Consortium of Investigative Journalists (ICIJ), a Washington, DC-based network of reporters and media organisations, said the files are linked to about 35 current and former national leaders, and more than 330 politicians and public officials in 91 countries and territories.
It did not say how the files were obtained, and Reuters could not independently verify the allegations or documents detailed by the consortium.
Jordan's King Abdullah, a close ally of the United States, was alleged to have used offshore accounts to spend more than $US100 million ($A137 million) on luxury homes in the United Kingdom and the United States.
DLA Piper, a London law office representing Abdullah, told the consortium of media outlets that he had "not at any point misused public monies or made any use whatsoever of the proceeds of aid or assistance intended for public use."
The Washington Post , which is part of the consortium, also reported on the case of Svetlana Krivonogikh, a Russian woman who it said became the owner of a Monaco apartment through an offshore company incorporated on the Caribbean island of Tortola in April 2003 just weeks after she gave birth to a girl.
At the time, she was in a secret, years-long relationship with Putin, the newspaper said, citing Russian investigative outlet Proekt.
The Post said Krivonogikh, her daughter, who is now 18, and the Kremlin did not respond to requests for comment.
Days ahead of the Czech Republic's October 8-9 parliamentary election, the documents allegedly tied the country's prime minister, Andrej Babis, to a secret $US22 million estate in a hilltop village near Cannes, France.
Speaking during a television debate on Sunday, Babis denied any wrongdoing.
"The money left a Czech bank, was taxed, it was my money, and returned to a Czech bank," Babis said.
The documents also showed how Indian businessman Anil Ambani and his representatives owned at least 18 offshore companies in Jersey, British Virgin Islands and Cyprus, according to the Indian Express, part of the ICIJ consortium.
Set up between 2007 and 2010, seven of these companies have borrowed and invested at least $US1.3 billion, the report said.
In 2020, following a dispute with three Chinese state-controlled banks, Ambani - the chairman of Reliance Group - had told a London court his net worth was zero.
Australian Associated Press
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