Although Putin is not personally named in the papers,they reportedly show some of his closest friends have made and concealed millions in ways that would have been assisted by his patronage.

Is it illegal to use an off-shore company?

No. There is nothing necessarily wrong with using an off-shore company. But use of such companies has been associated with attempts to conceal taxable income,or with money laundering. The leak also exposes the mechanisms used by some wealthy individuals to structure their affairs.

Are Australians involved?

About 800 wealthy Australian clients of Mossack Fonseca are being investigated by the Australian Taxation Office,theFinancial Reviewhas reported.

There are also extensivereferences to Australian banks in the documents.

An associate of former NSW Labor politician Eddie Obeid,George Ghossayan,is shown in the papers setting up an offshore partnership. And Dominic Galati,a sports promoter who once attempted to replace Frank Lowy as chairman of Football Federation Australia,was also setting up companies in Samoa.

There is,however,nothing necessarily improper about using off-shore firms.

What does Mossack Fonseca say?

The firm says it is legal and common to establish commercial entities in different jurisdictions for avariety of legitimate reasons.

"We are responsible members of the global financial and business community."