Finance ministers from 17 EU countries including Britain and Ireland have backed a declaration calling for global action to counter tax evasion.
They signed a joint statement at talks in Brussels warning that only a comprehensive worldwide system of exchanging tax information between national authorities will beat corporate tax dodgers.
"Tax evasion is a global problem and we should look for a global solution, otherwise the problem is simply displaced," said the statement.
Earlier Chancellor George Osborne told his colleagues the EU had to "take the fight" to tax cheats:
"There is an opportunity for Europe to take the fight to those who want to evade or avoid taxes...for European countries to give their backing to new global standards that Britain has been pushing for at organisations like the G8 and G7."
The issue is top of the agenda at an EU summit later this month and at a follow-up G8 meeting David Cameron is hosting in Northern Ireland in June.
The plan is to set a global standard for "multilateral automatic information exchange" - something currently hampered by banking secrecy and corporate confidentiality in some countries.
The signing involved Belgium, the Czech Republic, Denmark, Finland, France, Germany, Italy, the Netherlands, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Ireland and the UK .
It builds on a plan launched only last month by the UK, France, Germany, Italy and Spain to develop a pilot project for cross-border tax information exchange. Now pressure is on the other EU countries to join in when the issue is discussed again at next week's summit.
Although 11 member states did not sign on, the ministers agreed to mandate the European Commission to begin long-delayed negotiations on tax transparency with countries still operating strict banking and tax secrecy, such as Switzerland, Monaco, Andorra and Liechtenstein.