European Tax Commissioner Laszlo Kovacs said today he expected the bloc to wrap up a deal on a common corporate tax base within three years.
He said those countries that currently opposed such a move, seeing it as an attack on their sovereign right to fix fiscal policy, would come around.
"My assessment is three years if everything goes well," Mr Kovacs told a conference on EU policy in the Swedish capital when asked when the common corporate tax base would be ready.
He said a working group of senior officials was already looking at different ways that tax bases could be harmonised.
"At the moment there are 25 different ways to calculate the corporate tax base. . . . If we manage to have only one EU-wide set of rules that will increase competitiveness," he added.
He said 20 countries backed having such a single way of calculating corporate tax, with four or five other countries more reluctant.
"They are afraid that it is a Trojan horse to implement the harmonisation of tax rates at a later stage," he said. "We have no ambition and I have no personal ambition (to do that)."
His predecessor overseeing EU tax affairs, Dutchman Frits Bolkestein, made the original proposal on a common corporate tax base last year, and finance ministers agreed in September 2004 to study the possible launch of such a system.