While last November’s G20 summit in Cannes attracted most attention for addressing threats to the global economy and the eurozone debt crisis, one agenda item slipped by largely unnoticed, that could have major repercussions for Greek Australian taxpayers living in Australia.

At the summit, a ‘multilateral convention on mutual administrative assistance in tax matters’ developed jointly by the Council of Europe and the OECD (Organisation for Economic Co-operation and Development), was put forward to be signed by all G20 countries including Australia, and 21 others including Greece, in an effort to tackle tax evasion worldwide.

Last week the OECD announced that Greece has now signed the convention that gives participating countries a wide range of tools to enhance cross-border tax co-operation.

In a statement the OECD said: “At a time when Greece is looking to shore up its economy in line with a new financial package supported by the euro area countries and other stakeholders, the convention will allow Greece to work more closely with other countries to combat tax avoidance and evasion.”

OECD Secretary-General Angel Gurria added that, “in addition to demonstrating its commitment to following the international standards on tax transparency and exchange of information, this convention will help Greece improve its internal tax collection system and pursue the tax revenues lost to tax avoidance and evasion. This will ensure that individuals and multinational enterprises pay the right amount of tax, at the right time and in the right place.”

According to Neos Kosmos’ sources, on the basis of the new arrangement, the ATO may have already begun working with Greece in relation to the tax affairs of a number of Australians with Greek connections.

International taxation lawyer Tony Anamourlis, told Neos Kosmos that the affect of this new collaboration between the two countries could have major implications.

“I don’t think that people have taken this seriously. Greeks in Australia would never have thought that such a convention could have been signed, because they believe the Greek authorities are under no obligation to disclose and or provide information, but that has now changed dramatically,” says Mr Anamourlis.

Co-operation between the ATO and the Greek taxman will include sharing information on all aspects of tax liability.

“Because of the convention, this now obligates both tax authorities to provide, exchange and information about taxpayers’ income and assets – held both in Australia and in Greece,” added Mr Anamourlis.

“This goes across the board – general income tax, capital gains tax, property assets, rental income, interest, and dividends. In effect this will mean if either tax authority wishes to conduct an audit of an individual they can undertake this together.”

Information sharing could also include the supply of an individual’s (or company’s) Greek bank statements to the ATO, and could potentially affect means-testing for pensions in Australia.