Calls grew Monday for an end to the financial secrecy and shell companies that have allowed many of the world's richest and most powerful people to hide their wealth from tax collectors.

The outcry came after a report revealed the way that world leaders, billionaires and others have used offshore accounts to keep trillions of dollars out of government treasuries over the past quarter-century, limiting the resources that could be put to work helping the poor or combating climate change.

The report by the International Consortium of Investigative Journalists brought promises of tax reform and demands for resignations and investigations, as well as explanations and denials from those targeted.

The investigation, dubbed the Pandora Papers, was published Sunday and involved 600 journalists from 150 media outlets in 117 countries.

Hundreds of politicians, celebrities, religious leaders and drug dealers have hidden their wealth in shell companies and used other tactics to hide their investments in mansions, exclusive beachfront property, yachts and other assets, according to a review of nearly 12 million files obtained from 14 firms located around the world.

Many of the tax dodges are legal.

Gabriel Zucman, a University of California, Berkeley, economist who studies income inequality and taxes, said in a statement one solution is “obvious”: Ban “shell companies - corporations with no economic substance, whose sole purpose is to avoid taxes or other laws.”

“The legality is the true scandal,” the activist and science-fiction author Cory Doctorow wrote on Twitter. “Each of these arrangements represents a risible fiction: a shell company is a business, a business is a person, that person resides in a file-drawer in the desk of a bank official on some distant treasure island.”

The more than 330 current and former politicians identified as beneficiaries of the secret accounts include Jordan's King Abdullah II, former U.K. Prime Minister Tony Blair, Czech Republic Prime Minister Andrej Babis, Kenyan President Uhuru Kenyatta, Ecuador's President Guillermo Lasso, and associates of both Pakistani Prime Minister Imran Khan and Russian President Vladimir Putin.

The billionaires called out in the report include Turkish construction mogul Erman Ilicak and Robert T. Brockman, the former CEO of software maker Reynolds & Reynolds.

Some of those targeted strongly denied the claims on Monday.

“The new data leak must be a wake-up call,” said Sven Giegold, a Green party lawmaker in the European Parliament. “Global tax evasion fuels global inequality. We need to expand and sharpen the countermeasures now.”

Oxfam International, a British consortium of charities, applauded the Pandora Papers for exposing brazen examples of greed that deprived countries of tax revenue that could be used to finance programs and projects for the greater good.

“This is where our missing hospitals are,” Oxfam said in a statement. “This is where the pay-packets sit of all the extra teachers and firefighters and public servants we need.”

The European Commission, the 27-nation European Union's executive arm, said in response to the revelations that it is preparing new legislative proposals to enhance tax transparency and reinforce the fight against tax evasion.

The Pandora Papers are a follow-up to a similar project released in 2016 called the “Panama Papers” compiled by the same journalistic group.

The latest bombshell is even more expansive, relying on data leaked from 14 different service providers doing business in 38 different jurisdictions. The records date back to the 1970s, but most are from 1996 to 2020.

The investigation dug into accounts registered in familiar offshore havens, including the British Virgin Islands, Seychelles, Hong Kong and Belize. But some of the secret accounts were also scattered around in trusts set up in the U.S., including 81 in South Dakota and 37 in Florida.

Sen. Sherrod Brown, an Ohio Democrat who heads the Senate Banking Committee, decried “these gross abuses of our legal and tax system” which he said “enable criminals and fuel global inequality by allowing wealthy elites to avoid paying their fair share while working families are forced to make up the difference.”

The investigation found advisers helped Abdullah set up at least three dozen shell companies from 1995 to 2017, helping the Jordanian monarch buy 14 homes worth more than $106 million in the U.S. and the U.K. One was a $23 million California ocean-view property bought in 2017 through a British Virgin Islands company.

Abdullah denied any impropriety in a comment Monday by the Royal Palace, citing security needs for keeping the transactions quiet and saying no public funds were used.

U.K attorneys for Abdullah said he isn't required to pay taxes under his country's law and hasn't misused public funds. They said most of the companies and properties are not connected to the king or no longer exist, though they declined to provide details.

Blair, U.K. prime minister from 1997 to 2007, became the owner of an $8.8 million Victorian building in 2017 by buying a British Virgin Islands company that held the property, which now hosts the law firm of his wife, Cherie Blair, according to the the investigation. The two bought the company from the family of Bahrain's industry and tourism minister, Zayed bin Rashid al-Zayani. Buying the company shares instead of the London building saved the Blairs more than $400,000 in property taxes, the investigation found.

Cherie Blair said her husband wasn't involved in the purchase, which she said was meant to bring “the company and the building back into the U.K. tax and regulatory regime.” She also said that the “seller for their own purposes only wanted to sell the company,” which is now closed.

A lawyer for the al-Zayanis said they complied with U.K. laws.

The report also analyzed a transaction involving the British monarchy.

Britain's Crown Estate, the property business owned by Queen Elizabeth II, said it would review the 67 million-pound ($91 million) purchase of a London building from a company reported to be a front for the family of Azerbaijan's President Ilham Aliyev. The Guardian newspaper said the deal raised questions about whether the transaction should be investigated on money-laundering concerns. Aliyev, who has ruled Azerbaijan since 2003, has been accused of corruption and rights abuses.

The Crown Estate said it had conducted checks before the purchase but is now “looking into the matter” again.

Khan, the Pakistani prime minister, vowed in a tweet to recover the “ill-gotten gains” and said his government would look into all citizens mentioned in the documents and take action, if needed.

The report revealed Putin's image-maker and chief executive of Russia's leading TV station, Konstantin Ernst, got a discount to buy and develop Soviet-era cinemas and surrounding property in Moscow after he directed the 2014 Winter Olympics in Sochi. Ernst said the deal wasn't secret and denied suggestions he was given special treatment.

In 2009, Babis, the Czech prime minister, put $22 million into shell companies to buy a chateau property in a hilltop village in Mougins, France, near Cannes, the investigation found. The shell companies and the chateau were not disclosed in Babis' required asset declarations, according to documents obtained by the journalism group's Czech partner, Investigace.cz.

Babis has denied any wrongdoing. He said the report was meant to harm him ahead of the Czech Republic parliamentary election being held on Friday and Saturday.

The Czech police's organized crime unit said it would launch an investigation.

Montenegro's President Milo Djukanovic faced calls to resign after the local Montenegrin Network for the Affirmation of the Non-Governmental Sector alleged he and his son established a trust to conceal their wealth behind a complicated network of companies. His office denied the report.

Liedtke reported from San Ramon, California, and Mattise reported from Nashville, Tennessee. Associated Press writers Paul Wiseman and Marcy Gordon in Washington, Barry Hatton in Lisbon, Portugal; Karel Janicek in the Czech Republic; Frank Jordans in Berlin; Josef Federman in Jerusalem; John Rice in Mexico City, Kathy Gannon in Islamabad, Pakistan, and Felicia Fonseca in Phoenix contributed to this report.