The queue of countries knocking on the door of the European Union will get a little longer tomorrow when Albania formally submits its membership application. But the prospects of joining the 27-strong group have seldom been more complex, with some of the biggest member states turning their faces firmly against enlargement.

Angela Merkel, the German Chancellor, has called for a pause in expansion and, with President Sarkozy of France, has warned that, without the Lisbon treaty, there can be no further admissions after Croatia, which is next in line.

The treaty aims to streamline and reorganise the workings of the EU to cope with the 2004 and 2007 entries, which brought membership from 15 to 27. The Irish rejected the treaty in a referendum last year and are expected to vote again in the autumn.

But it is becoming clear that the treaty will not put enlargement back on track. Croatia was scheduled to join next year but its progress has faltered, mainly over a dispute with Slovenia, the only former Yugoslav country to join so far. A conference to sort out the row – over territorial waters – was called off last week and diplomats are frantically trying to break the impasse. Croatia's entry date has probably slipped to 2011.

France and Germany are keen to let Croatia in but behind their objections to further expansion lies a concern about the affordability of admitting yet more impoverished and dysfunctional countries. There is also an underlying fear in Paris and Berlin that to admit Turkey – which has had formal candidate status since 1987 – would be a step too far. Turkey would become the largest member within a few years of joining, giving it more MEPs than Germany and changing the dynamics of the bloc.

But even if, as Mr Sarkozy has suggested, Europe has “natural borders” – which include the Balkans but exclude Turkey – the experience of Romania and Bulgaria's accession in 2007 has made a number of other countries wary of further expansion.

It is widely accepted that the membership process was bungled in a rush to bind Bucharest and Sofia to the West. There was not enough insistence on internal reforms to safeguard the enormous sums of EU money set to pour into the two former Communist nations for large infrastructure and modernisation projects. Not a month goes by without fresh controversy over corruption.

This has led to greater scrutiny of the current candidate countries – Croatia, the Republic of Macedonia and Turkey – and the potential candidates – Albania, Bosnia Herzegovina, Kosovo, Montenegro and Serbia.

Iceland will be given an easier ride should it decide to apply after a pro-EU victory in its recent election, but it is a special case because of its more developed structure and its tiny population of 320,000. Generally, the potential members are a long way off meeting EU expectations of transparency, rule of law and reform.

The sound of the drawbridge being pulled up has alarmed member states such as Britain and Sweden, which are firmly committed to greater expansion, as well as observers such as the World Bank.

Robert Zoellick, the bank's President, warned that the prospect of EU membership was the main driver of progressive reform in some countries in such troubled financial times. Speaking of Serbia, he said: “The way they can keep on a peaceful and constructive course is to say that there is a pathway to Europe. That is true for the other Balkan countries.” He added that not offering these countries the possibility of accession would put the region on “a very dangerous course”.

In Ukraine, he added, the hope of joining the EU would be the antidote to the “great political division” gripping the country.

But the French and Germans are so worried about the impact of further enlargement on sceptical voters at a time of financial belt-tightening at home that they did not even want to be seen helping along the candidature of tiny Montenegro (population 680,000). The next stage in the process – the referral of Montenegro's formal application to the European Commission for assessment – was finally agreed last week after months of stalling.

To put as much distance as possible between it and Paris and Berlin, the move was sneaked through, bizarrely, under any other business at a meeting of fisheries ministers.

http://www.timesonline.co.uk/tol/news/world/world_agenda/article6180257.ece