Ten eurozone countries have agreed on some aspects of a harmonised tax on financial transactions.
They want to finalise a deal by the middle of next year to reach on remaining issues.
No agreement has been struck as yet on tax rates.
The countries include Germany, France, Italy, Belgium, Greece, Portugal, Slovakia, Slovenia, Spain and Austria.
Estonia decided not to take part because its banks largely trade in shares issued out this group of countries and so there would be little revenue to collect.
A 2013 European Commission proposal suggested a 0.1 percent levy on share and bond trades and 0.01 percent on derivatives trades.