Work is underway to crack down on multinational companies that are dodging tax - but any law changes are still months away.

Websites like Facebook and Google have been pinged for arranging their tax affairs, to pay as little as possible in the countries where they have bases.

The OECD's working together to tackle the issue, but its recommendations for should be done are still more than a year away.

Inland Revenue has told its minister there's no need to wait for the OECD to act, suggesting large companies should have to file tax returns earlier so their information can be analysed for any loopholes.

IRD's also suggested a voluntary code of practice for corporations to "avoid aggressive tax planning" and have a "transparent relationship" with tax authorities.