Panama is creating an international panel to help improve transparency in its offshore financial industry.

The move follows the leak of millions of documents from law firm Mossack Fonseca, showing it helped some clients evade tax and avoid sanctions.

Several countries are probing possible financial crimes by the rich and powerful in the aftermath of the leak.

President Juan Carlos Varela said Panama would work with other countries over the revelations.

"The Panamanian government, via our foreign ministry, will create an independent commission of domestic and international experts," he said in a televised address.

The panel, he said, would examine working practices and propose measures that could be shared to strengthen the transparency of the financial and legal systems.

Correspondents say the president is eager to defend his country against a "media attack" by wealthy countries that he says are unfairly stigmatising him following the leak.

Mossack Fonseca, for its part, says that it has been the victim of a hack.

Mossack Fonseca says it has never been charged with any wrong-doing. Photo: Reuters

Mossack Fonseca partner Ramon Fonseca insisted the leak was not an "inside job" - the company had been hacked by servers based abroad.

It has now filed a complaint with the Panamanian attorney general's office.

Fonseca served as a minister in the government of current President Juan Carlos Varela but stepped aside earlier this year after separate allegations linked the firm to the corruption scandal engulfing the Brazilian state oil company Petrobras.

Mossack Fonseca's Brazilian arm was accused of helping several of those accused in the Petrobras case of opening offshore companies in Panama in order to launder money through property transactions.

Fonseca said he had stepped aside "to defend my honour and my firm" and denies any wrongdoing on the part of his firm in the Petrobras case.

Fonseca said the "only crime" that had been committed was the hack of his firm's servers. Photo: Reuters

Varela has been quoted in Panamanian media as saying that he is still in touch with Mr Fonseca, calling him a "friend".

"At difficult times friends do not run away, they are there," Varela said.

Mossack Fonseca has accused media organisations reporting the leak of having "unauthorised access to proprietary documents and information taken from our company" and of presenting this information out of context.

The revelations have already sparked political reaction in several countries where high-profile figures have been implicated.

On Tuesday Iceland's Prime Minister Sigmundur Gunnlaugsson stepped down after the documents showed he owned an offshore company with his wife but had not declared it when he entered parliament.

The ruling coalition has named Sigurdur Ingi Johannsson as the new prime minister, with early elections to be held in the autumn.

Gunnlaugsson says he sold his shares to his wife and denies any wrongdoing.

Panama Papers - tax havens of the rich and powerful exposed

• Eleven million documents held by the Panama-based law firm Mossack Fonseca have been passed to German newspaper Sueddeutsche Zeitung, which then shared them with the International Consortium of Investigative Journalists. BBC Panorama and UK newspaper The Guardian are among 107 media organisations in 76 countries which have been analysing the documents. The BBC does not know the identity of the source
• They show how the company has helped clients launder money, dodge sanctions and evade tax
• Mossack Fonseca says it has operated beyond reproach for 40 years and never been accused or charged with criminal wrongdoing
• Tricks of the trade: How assets are hidden and taxes evaded
• Panama Papers: Full coverage; follow reaction on Twitter using #PanamaPapers; in the BBC News app, follow the tag "Panama Papers"