France's powerful Foreign Minister, Bernard Kouchner, said today that he had turned against the idea of allowing Turkey to join the European Union because of Ankara’s behaviour at last week’s Nato summit.

Mr Kouchner, who came to prominence as co-founder of Medecins sans Frontieres, made the comment as Barack Obama - speaking to a gathering of students in Istanbul on the final event of his eight-day European tour - called once again for Turkey to be granted EU membership.

President Sarkozy has long been opposed to Turkey’s EU bid and that has been official French policy, but his left-wing Foreign Minister had been more open to the idea - at least until Saturday's summit in Strasbourg.

“Turkey’s evolution in, let’s say, a more religious direction, towards a less robust secularism, worries me,” the minister told RTL radio.

Mr Kouchner said that he had been surprised when Turkey’s delegation to the Nato summit had initially refused to accept the appointment of Anders Fogh Rasmussen, the Danish Prime Minister, as the alliance’s new Secretary-General. Mr Rasmussen made enemies in the Muslim world in 2005 when he defended the freedom of expression of Danish cartoonists who mocked the Prophet Muhammad.

The Turkish President, Abdullah Gul, delayed Saturday's summit by refusing to accept his nomination and only dropped his veto threat after Mr Obama brokered a compromise deal under which Mr Rasmussen will have a Turkish deputy.

“I was very shocked by the pressure that was brought on us,” Mr Kouchner said.

After the Strasbourg summit, Mr Obama ruffled some feathers in Europe by explicitly backing Turkish membership of the EU - prompting a sniffy rebuke from Mr Sarkozy that that would be Europe's decision, not America's.

In Istanbul today, Mr Obama was asked about Mr Sarkozy's comments. "It is true that the United States is not a member of the EU, so it's not our decision to take, but that doesn't prevent me fro having an opinion," he replied.

"I've noticed that the Europeans have a lot of opinions about US policy for a long time and they've not been shy about expressing them. That's what friends do."

He added: "If Turkey can be a member of Nato and send its troops to help protect and support its allies and its young men are put in their way, I don't see why you should not also be allowed to sell apricots to Europe or have more freedom to travel."

Once again, Mr Kouchner echoed his boss. “It’s not for the Americans to decide who comes into Europe or not,” he said. “We are in charge in our own house."

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