Mandelson calls for end to two-centre European Parliament

Peter Mandelson has broken ranks with his European Commission colleagues with an outspoken attack on the "rigmarole" of the European Parliament's monthly commute from Brussels to Strasbourg, describing it as "unacceptable".

The British trade commissioner has also suggested that any revived version of the European constitution that requires referendums across the continent was doomed to failure.

His comments are likely to intensify debate over the site of the European Parliament, which moves from Brussels to Strasbourg one week in every four. The move costs the European taxpayer an estimated €200m (£140m) each year.

Asked about this last month, Mr Mandelson's boss, the European Commission President, Jose Manuel Barroso, refused to comment.

But, in an interview with E!Sharp magazine, Mr Mandelson came out firmly against the commute. He said: "I like going to Strasbourg. I like the Parliament in Strasbourg. But it is very hard to justify the expense. Such a cost, such rigmarole, is unacceptable to public opinion and we have to recognise that." Agreed in 1992 by heads of government including John Major, the Parliament's travel arrangements are enshrined in EU law. But there is growing pressure on national leaders from their MEPs to change the system.

That intensified when senior MEPs discovered the city of Strasbourg may have been overcharging them for the Parliament's site for the past 25 years, and that as much as €2.7m of taxpayers' money could have been kept by the Alsace municipality last year. The Parliament's president and the leader of its second largest group have suggested a rethink. But supporters are waiting until after France's presidential elections next year before pressing the issue. They hope that, if Nicolas Sarkozy wins the contest, he could be persuaded to abandon the Parliament's Strasbourg week. In exchange, the city might get a new European Institute of Technology (EIT), helping boost the role of Strasbourg as an international centre of technology and learning, and might be home to a new European Research Council or, alternatively, the venue for summits of EU heads of government.

On the European constitution, Mr Mandelson, an architect of New Labour's makeover in the 1980s, said changing its name is insufficient. He said: "If your product is deficient then you have to attack the substance, not the wrapping." Last month, EU leaders gave themselves a deadline of the end of 2008 to decide what should happen to the European constitution. Mr Mandelson suggested any new text requiring a referendum was doomed.

He said: "Anything that crosses the threshold of requiring a referendum will immediately run into difficulties. We have to come to terms with the fact that getting any constitutional treaty past a referendum in our member states will be an uphill struggle.

"A mixture of national discontents, populist tides and currents, and the fact that in a referendum there are 101 different issues on which the public will vote, will tell you to question whether any referendum is likely to be successful."

He added: "I don't think it is susceptible to quick fixes. I am tempted to argue that we should identify those elements of the existing draft treaty that are the most necessary and most important and effective in meeting our institutional needs and strip away the rest."