World leaders have scrambled to react to the leak of a trove of documents linking many of them to secretive offshore companies that enabled vast sums of money to move around the world hidden from law enforcement and regulators.
A massive report called The Panama Papers, published simultaneously by multiple news organizations in multiple languages on April 3, divulged details about the offshore holdings of 12 current or former heads of states, including Ukrainian President Petro Poroshenko.
The leaked documents from the Panamanian law firm Mossack Fonseca also revealed that relatives or associates of 17 other current or former leaders held offshore accounts, including Russian President Vladimir Putin.
Several world leaders on April 4 confronted the report head-on, saying the report did not reveal anything implicating them in wrongdoing.
Poroshenko took to Facebook to defend himself after the leaked documents reportedly showed that he moved his confectionary business, Roshen, to the British Virgin Islands in August 2014 amid some of the heaviest fighting between Kyiv's forces and Russia-backed separatists.
"Having become president, I recused myself from the management of my assets and delegated this to the respective consulting and law firms," Poroshenko wrote. "I expect that they will provide all necessary details to the Ukrainian and international media."
He added that he took the issues of income declaration, paying taxes, and conflicts of interest "very seriously" and was in "in full compliance with the Ukrainian and international private law."
Earlier in the day, the head of Ukraine's populist Radical Party called for an impeachment investigation of Poroshenko over allegations he used the offshore account to avoid taxes. Ukraine's Prosecutor-General's Office said it had seen no evidence that Poroshenko committed a crime based on the leaked documents.
In Moscow, meanwhile, the Kremlin slammed the leak of the tax documents as an attack aimed primarily at Putin.
Putin is not named in the leaked documents. But the report claims to have documented a vast network of shady money transfers, several of which it details, used by close associates of Putin to funnel as much as $2 billion into offshore shell companies.
"Putin, Russia, our country, our stability and the upcoming [parliamentary] elections are the main target, specifically to destabilize the situation," Kremlin spokesman Dmitry Peskov told reporters on April 4.
He added that there was "nothing new or concrete" about the Russian leader in the leaks and suggested that U.S. intelligence was behind the revelations.
"We know this so-called journalist community," Peskov said. "There are a lot of journalists whose main profession is unlikely to be journalism: a lot of former officials from the [U.S.] State Department, the CIA, and other special services."
The information stems from millions of e-mails, spreadsheets, corporate records, and others materials leaked from Mossack Fonseca, a Panama-based law firm with representatives in dozens of countries that specializes in setting up shell companies, the report says.
WATCH: Muscovites React To 'Panama Papers' Implicating Putin
The leaked data was initially provided to the German newspaper Suddeutsche Zeitung. It was then shared with the International Consortium of Investigative Journalists (ICIJ), based in Washington, which collaborated with media outlets around the world over the course of a year to organize, analyze, and publish the materials.
There was no immediate response from Azerbaijani President Ilham Aliyev, whose wife was reportedly named in the leaked documents as one of two managers of a Panamanian offshore firm in 2005, a firm that in turn has control of the Azerbaijani conglomerate AtaHolding.
Among the assertions in the report is that Aliyev's daughters controlled a Panamanian firm that held a significant stake in a group of companies developing Azerbaijani gold fields.
Russian President Vladimir Putin (left) and Leyla Aliyeva, daughter of Azerbaijani President Ilham Aliyev, are implicated in the leaks.
Iceland's prime minister, meanwhile, insisted that he would not resign after the investigation revealed tax documents suggesting that he and his wife used an offshore company to hide million-dollar investments.
"I have not considered quitting because of this matter nor am I going to quit because of this matter," Prime Minister Sigmundur David Gunnlaugsson told Icelandic television Channel 2.
He denied any wrongdoing and denounced the leak of the documents as a witch-hunt against him and his wife.
"She has been adamant about paying taxes on [the offshore firm] to Icelandic society rather than saving money by paying taxes abroad," he said.
The British government has requested a copy of the leaked data, which could prove embarrassing for Prime Minister David Cameron, who has been a vocal critic of tax evasion.
His late father, Ian Cameron, is mentioned in the documents, as are members of the prime minister's Conservative Party in the upper house of parliament, former Conservative lawmakers, and party donors, according to British media reports.
"We will closely examine this data and will act on it swiftly and appropriately," said Jennie Granger, director-general of enforcement and compliance at the British Revenue and Customs.
Cameron's spokeswoman declined to comment on whether the prime minister's family had invested in offshore entities set up by his father, calling it a "private matter."
With reporting by RFE/RL's Ukrainian Service, Reuters, UNIAN, AFP, and AP