G20 governments will need to find great political courage if they are to curb multinationals' multi-billion tax dodging, campaigners warn today.

Christian Aid, ActionAid International, Oxfam, the Global Alliance for Tax Justice, Tax Justice Network, Tax Research UK and others say governments' attempts  to curb the epidemic of tax evasion and avoidance will only succeed if politicians stand up to lobbying by the powerful companies and individuals who benefit hugely from the status quo.

Their warning comes in a new briefing endorsed by 34 organisations and published in the run-up to G20 countries' summit meeting in St Petersburg on 5^th and 6^th September.

Alex Prats, Principal Economic Justice Adviser at Christian Aid, said: ‘Almost every day, we get new evidence that aggressive tax avoidance and sometimes evasion are now the norm for large multinational companies, not the exception. They are making billions from these activities, while ordinary people — especially in poor countries - pay the price in higher taxes and worse public services.

‘G20 and other governments have around two years in which to prove whose side they are really on.'

The new briefing argues that governments should explore a range of possible ways to make multinationals pay their fair share. James Henry, Chair of the Global Alliance for Tax Justice, said: ‘The G20 and other governments, as well as the OECD, should explore credible alternatives to the existing rules. At present, despite its good intentions, the OECD seems to be trying to save an international corporate tax system which is fundamentally flawed.'

Richard Murphy of Tax Research UK said 'This plan recognises the progress made by the BEPS programme, but also makes clear that it falls a long way short of the reform that is really needed - including full country-by-country reporting by multinational corporations.'

In July, the OECD published an Action Plan on Base Erosion and Profit Shifting (BEPS) by multinational companies.

Campaigners' new briefing encourages policymakers to pursue a rigorous study of the merits, risks and feasibility of alternatives to the OECD's existing rules, such as unitary taxation and formulary apportionment.

In addition, it urges the OECD and G20 countries to do more to include poor countries in the BEPS discussions on making multinationals pay their fair share.

Maria Villanueva, policy advisor at Oxfam, said: Maria Villanueva, policy advisor at Oxfam, said: ‘The people hardest hit by multinational tax dodging are poor people in developing countries. Developing countries can't compete with corporations' sophisticated methods of tax dodging and lose billions every year in potential revenues. This is a disaster for people living in poverty.

‘The OECD and G20 countries should urgently ensure that developing nations are included as equal partners in the international search for solutions — not just asked to rubber-stamp plans agreed elsewhere. So far, with the exception of the BRICS, this has not happened.'

A third part of the briefing looks at what else governments must do, beyond the OECD BEPS Action Plan, to curb the financial secrecy which sustains tax evasion, corruption and money laundering across the world. Reforms such as automatically exchanging tax information between governments and greater transparency around the identities of the real owners of multinationals and what the companies do in each country where they work must become the norm.

The full briefing is available here.