Verhofstadt: EU verder zonder Verenigd Koninkrijk (en)

The EU should go ahead and further integrate without the UK if it attempts to block a new constitutional treaty, Belgium's prime minister Guy Verhofstadt has said.

In an interview with German daily Die Welt, he said he expected the German EU presidency "not just to have put down a roadmap for the new constitution by the end of June, but also an outline of the content."

"Only then is it guaranteed that an intergovernmental conference will really be short and that the necessary changes can go into force by the upcoming European election in summer 2009."

Asked about what the EU should do if the UK blocks an agreement on a new treaty, Mr Verhofstadt said "then the train has to drive on anyway."

"Should the British government block the new attempt for agreement on the constitutional treaty, then the European Union must progress without Great Britain."

The prime minister, who has one of the most federalist visions among EU leaders today, said that while a two-speed Europe is "is not an ideal picture," if it is not possible to get all countries on board for further integration then those that want to should push through "more cooperation in economic, social and justice policy within the euro-zone."

Drawing parallels from across the Atlantic, he said "the United States of America also did not come about in unison. At the time, only nine of the 13 British crown colonies voted in favour. The rest tailed behind and accepted the agreement later."

The Belgian leaders words come as EU leaders gather in Brussels today with part of their discussions this evening to be devoted to drawing up a text to celebrate the 50th anniversary of the founding Treaty of Rome later this month.

The text is being seen as a precursor to discussions on the EU constitution itself with Berlin already struggling to get this short document to a state that is acceptable by all 27 governments.

Meanwhile, Germany is also sounding out opinions on the constitution - rejected in two referendums in 2005 - and aims to have its ideas on the table by its end-of-presidency summit in June.

However its efforts to get a clear picture are being hampered by the political uncertainty in France, which is facing elections in April and May, as well as by the UK, indicating that it would be happier without any new constitution at all.