European leaders are due to fly an extra 77,000km (48,000 miles) collectively simply to sign the new treaty.

The document was supposed to herald a brave new dawn for Europe. But plans for the 27 leaders to add their signatures have triggered an old-fashioned diplomatic row.

Portugal and Belgium have been accused of “pathetic vanity” for refusing to compromise over the location of the signing ceremony, a stance that will leave Europe’s skies cluttered with the private planes of prime ministers.

The argument boils down to national pride. Portugal, current holder of the EU’s rotating presidency, wants to preside over the signing, arguing that it oversaw all the tricky negotiations. It is also keen for the document — the EU reform treaty — to go down in history as the “Lisbon Treaty”.

Belgium disagrees. The signing is in the diary for December 13, the first day of the EU’s six-monthly summit. Since Nice in 2001 these summits have been held in Brussels, and Belgium does not want to lose its host status and the lucrative spin-offs that go with it.

The upshot is that instead of making simple return trips to Brussels from their home capitals, 26 EU leaders as well as José Manuel Barroso, the Commission President, will have to fly first to Lisbon, where they will spend a matter of hours, and then reboard their planes and follow one another to Brussels, where by evening they will be sitting together again around a different table.

The Times has calculated that the minimum extra air travel is 77,000km — and will be much more if foreign ministers, who are also required to sign the treaty, travel separately from their leaders.

“They could not have handled it worse — just when we have got a treaty to improve the EU, we have to keep the Portuguese happy by signing in Lisbon and the Belgians happy by keeping the summit in Brussels,” an EU diplomat said yesterday.

The signing ceremony, due to last for about an hour, will start the process of national ratification which, in Britain, will be through Parliament after the Government ruled out a referendum. Exasperated diplomats are keenly aware that this battle of national egos is undermining the treaty’s supposed main selling point — that it would help to improve EU decision-making so that leaders can move on to issues that really matter, such as climate change.

At a meeting of senior officials the Italians called for the whole summit to be held in Portugal. The Belgian representative reportedly replied: “No way.” As a result the replacement for the EU constitution will start life under attack from environmentalists for the size of its carbon footprint, which The Times has conservatively calculated at 135 tonnes of extra CO2 at a time when the EU is purporting to lead the world on targets to cut greenhouse gases.

Sonja Meister, of Friends of the Earth, said: “Of course, people have to travel for international events, but the EU should try to avoid situations like this and think practically and in terms of its own promoted policies.”

British diplomats have suggested a surprising solution — for the treaty to be signed before the EU/Africa summit in Lisbon on December 8-9, the week before Portugal’s planned ceremony, when most EU leaders will be there anyway. It is surprising because Gordon Brown, the Prime Minister, has vowed to boycott that meeting if, as expected, the Portuguese waive an EU ban to allow President Mugabe of Zimbabwe to attend.

A British diplomat argued that, to avoid the unnecessary shuttle flights for all 27 leaders between Lisbon and Brussels on December 13, Mr Brown would be prepared to fly to the Portuguese capital to sign the treaty on December 7 and would simply leave if Mr Mugabe showed up.

But the Portuguese appeared to dismiss the idea, suggesting that the final bound copies of the treaty in all 23 EU languages would not be ready by then. “One thing is decided: the signing will be on December 13,” said a spokeswoman for the Portuguese Government. “The Cabinet of the Prime Minister is talking with everybody, all the member states, so I think we will find a solution. The member states must agree with each other.”

To add to the confusion, Angela Merkel, the German Chancellor, is understood to have argued that the decision is up to the Portuguese presidency, not member states.

Neil O’Brien, director of the Open Europe think-tank, said: “This is Europe at its ridiculous worst. EU leaders are squandering vast amounts of taxpayers’ money and emitting huge amounts of carbon purely because of the pathetic vanity of the Belgians and Portuguese.”

Francisco Duarte, of Portugal’s Foreign Ministry, said: “The logistics question is becoming a political question. We want to sign the treaty in Lisbon. It is very important for us and it would be an honour to organise the whole summit here. But Belgium is keen not to set a precedent. If no one gives in, we will most likely see a lot of travelling.”

Frequent flyers

77,000 extra kilometres will be flown by EU heads of government in order to sign the treaty in Lisbon

27 private jets flying that distance produce more than 135 tonnes of carbon dioxide

135 tonnes of C02 is 60 times the combined weight of all EU heads of government

200 trees, a small copse, would be required to offset the carbon fumes from the travels of the heads of government

The wood from those trees would provide enought paper to print 2,800 copies of the 250-page EU treaty iin each of the EU's 23 official languages

After signing the treaty, the leaders will head for Brussels

Sources: European Union; University of California, Berkeley; Energy Savings Trust; carbonneutral.com . All numbers are approximate

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