Istanbul is haunted by a unique type of melancholy, Orhan Pamuk writes in his wondrous book on Turkey's largest city. Known as hüzün, "the black mood shared by millions of people together" is particularly dense on cold winter mornings "when the sun suddenly falls on the Bosphorus and the faint vapour almost rises from the surface".

Many Turks must be overcome by a comparable weariness (this one not mitigated by beautiful scenery) when they hear of their country's never-ending quest for membership of the European Union. More than 22 years after Turkey first applied to join, the prospect of its EU entry seems as remote as ever, even if formal accession talks began in 2005.

With progress in those negotiations already sluggish, primarily because of unresolved questions over the future of Cyprus, there is now a new hurdle to be overcome. Bulgaria has indicated it will block Turkey's membership unless compensation is paid for the expulsion of Thracians by Ottoman forces in the early 20th century.

It is only right that Turkey should be required to improve its human rights record in order to join the union. The aforementioned Pamuk is among those to have fallen victim to its restrictions on free speech; the Nobel laureate was prosecuted over a 2005 interview in which he discussed the genocide perpetrated by Ottoman forces against 1.5m Armenians nine decades earlier. While charges against him were eventually erased on a technicality and while important gestures of friendship towards Armenia have been made by the present Turkish leadership, the Ankara authorities continue to muffle voices of dissent. This has been illustrated by a ruling from the Turkish constitutional court last month, banning the Kurdish Democratic Society party.

Such curbs on expression, however, have nothing to do with the antipathy directed at Turkey by Nicolas Sarkozy in France and Angela Merkel in Germany. Rather, their opposition to Turkey's bid for EU membership is explained by what a columnist in the Turkish newspaper Hürriyet accurately described as "basic facts not pronounced openly" on Monday. "Turkey is a Muslim country," Mehmet Ali Birand wrote. "And Europe is not ready yet to accept a Muslim country in the EU."

This anti-Turkish bias is tantamount to racism. Even though the EU institutions officially claim to cherish diversity, there is a tacit agreement among some of their most powerful leaders that the union must remain predominantly Christian. Herman Van Rompuy, the EU's new president, is one of the few to have voiced this desire in a public forum (and that was long before his recent elevation in status). "The universal values which are in force in Europe, and which are also fundamental values of Christianity, will lose vigour with the entry of a large Islamic country such as Turkey," he told a meeting at the Belgian parliament in 2004.

As a Christian myself (albeit not a devout one), I am not sure what teachings of the poor Nazarene that Van Rompuy professes to follow provide a justification for slamming the door on adherents to another faith. If a golf club adopted a similar policy of exclusion, there is a strong likelihood it would be sued for breaching equality laws. The EU is nominally a club of democracies; why is it allowed to discriminate on religious grounds?