France has been singled out for criticism for derailing the process of Turkey’s accession to the EU and damaging its internal reforms in a report for the European Commission which calls for a return to serious negotiations on full membership for Ankara.

Nicolas Sarkozy, the French President, was criticised for “negative statements” such as his call for partnership rather than integration with the EU, which have seen Turkish reformers lose momentum as the country’s future is left in limbo.

A vicious circle has been created as a result of snubs from France, Germany and Cyprus which has seen reform go into reverse and given further ammunition to those who oppose Turkey’s EU membership, said Martii Ahtisaari, the Nobel laureate and head of the Commission on Turkey.

Mr Ahtisaari also urged Turkey and Greece to use all their influence to bring about a positive conclusion to talks about the reunification of Cyprus, which he described as standing the best chance of success in a generation, which could give a massive boost to Turkey’s EU chances.

The former Finnish President warned that the EU’s credibility as a reliable partner not just with Turkey but in the world at large was at stake over its approach to Ankara. This was because a unanimous decision of the EU leaders to forge ahead with accession talks in 2004 was quickly followed by calls from Mr Sarkozy for Europe to draw its borders before the Bosphorus and talk from Berlin of a privileged partnership rather than membership.

Turkey first applied to join the EU in 1987, signed a customs union agreement in 1995 and has been an official candidate to join since 1999. But no end date is in sight and key areas of the negotiations remain blocked by EU member states, while both France and Austria have vowed to hold referendums before allowing Turkey to join.

Meanwhile, ten former Communist countries have joined to EU following the fall of the Berlin Wall, as well as Cyprus and Malta in 2004, while Croatia, which applied in 2003, is set to join in 2010 or 2011, probably with Iceland if it confirms its application. The former Yugoslav Republic of Macedonia applied in 2005 and looks likely to overtake Turkey too.

“Unfortunately, negative statements by some European leaders soon after the EU’s Heads of Government had taken their unanimous decision , efforts to substitute alternative arrangements to accession as the agreed objective and obstacles put in the way of the negotiations have all but derailed the process,” the Commission on Turkey report concluded.

“In Turkey, this led to a dramatic drop in support for EU convergence from the Turkish public and reinforced the government’s lack of resolve in proceeding with Turkey’s transformation. This, in turn, fed arguments to the sceptics in European countries for whom the lack of reforms presented the proof that Turkey was unworthy of EU membership.

“The Independent Commission is of the view that the vicious circle thus created must be broken urgently, in the interest of both Turkey and the European Union.”

Mr Sarkozy is singled out for criticism: “France has publicly declared that it will not allow five key areas of the negotiations to go forward, specifically because the current French leadership opposes Turkish accession and believes Ankara should be offered ‘partnership, not integration’.”

The EU has formally opened 11 of the 35 negotiating chapters with Ankara. Eight other chapters have been frozen since 2006 due to a customs dispute with Cyprus, which has been divided between ethnic Turkish and Greek sides since 1974.

The report also warned Turkey to do more to rekindle the reform process. “Turkey, including both its government and opposition, has to encourage its many supporters in Europe through a dynamic, broad-based reform process, thus confirming that it is willing and serious in its ambition to join the EU.”

Ahmet Davutoglu, the Turkish Foreign Minister, warned countries hostile to Ankara’s EU application that their opposition was planting “doubts” in the minds of Turks and slowing the pace of reform.

“The negative voices that we keep hearing from some countries in the EU just spread doubt among our citizens and impede our efforts to continue reforms,” he wrote in an opinion piece in Sweden’s Dagens Nyheter.

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