By Kirsty Hughes
European affairs analyst
The EU's membership negotiations with Turkey have barely started but already worries are surfacing in Brussels and London that they could collapse within months.
No-one thought the talks would be easy - but what is driving such fears of an early breakdown? The answer is Cyprus.
The EU has been playing a difficult juggling act with both Turkey and Cyprus, but it may be about to drop some of the balls.
Cyprus joined the EU in 2004, despite the fact that the island was still divided, its "green line" patrolled by UN soldiers, and with EU laws unable to apply to the Turkish Cypriot north.
Last October, the EU agreed to start membership negotiations with Turkey, although Ankara does not recognise the Republic of Cyprus, and has troops in northern Cyprus.
For now, there are no peace talks over Cyprus. Since the Turkish Cypriots voted "Yes" and the Greek Cypriots "No" to a UN peace plan in April 2004, the UN has been reluctant to re-engage.
But while the Cyprus problem stagnates, EU-Turkey talks are moving ahead.
Negotiations will start within weeks on the first two "chapters" - research, and education. EU diplomats are relatively upbeat, despite concerns on freedom of expression and freedom of religion.
However, the scene looks set to darken this autumn.
Turkey and Cyprus are engaged in a cat-and-mouse act over whether Turkey will recognise the Republic of Cyprus without the Greek Cypriots moving to end the isolation of northern Cyprus and to restart peace talks.
Turkey last July signed the so-called Ankara protocol extending its customs union deal to the 10 new EU member states including Cyprus.
But it insisted this did not amount to recognition and it bars Greek Cypriot shipping and planes from its ports and airports.
Unless Turkey opens its ports it will fail a review of its compliance with the customs union and its bilateral relations with other member states, due this autumn.
The review was agreed by the EU last September under pressure from France and Cyprus. But even Britain, one of Turkey's strongest supporters in Europe, says Turkey has to give in on the ports question, in order to pass.
Turkey's ambassador to the EU, Volkan Bozkir, does not sound ready to comply. He says it is a political issue, not simply a question of implementing the customs union.
"Unless political circumstances are altered, it will be difficult for any move on that particular field," he says.
But Cyprus's permanent representative to the EU, Nicos Emiliou, says that, on the contrary, the customs union commits Turkey to opening its ports. Its demand for concessions is therefore a case of "trying to get something for nothing".
Member states have less leverage over Cyprus now it is inside the EU
Cyprus may call for a strong response to the report on Turkey's compliance this autumn, even an overall suspension of negotiations (though this would need to be agreed by all 25 member states).
"If the situation has not changed, it would be a very serious breach by Turkey of obligations it has willingly taken in good faith," Nicos Emiliou says.
Without the opening of Turkish ports, he adds, "the overall progress of Turkey's negotiations will be affected.
"It presupposes a very serious political discussion perhaps at the highest level."
Problems will also start when EU negotiations reach issues linked to the ports - again, probably in autumn.
Some wonder quietly if the threat of formal recognition of the north could push the Greek Cypriot side back to the negotiating table
Nicos Emiliou says: "It would be inconceivable for us and for a big number of other member states to open chapters like customs union or transport or free movement of goods, if Turkey has not complied with obligations under the protocol."
If a lot of chapters are blocked, negotiations could soon stall.
Most EU diplomats and politicians do not want talks with Turkey to collapse in acrimony.
They do want to see Turkey open its ports to Greek Cypriot vessels, but they also want moves to resolve the Cyprus problem.
Diplomats fear Cyprus is freezing out the UN to avoid compromising
But the Cypriots have much more bargaining power vis-a-vis Turkey now they are inside the EU, and the other EU member states much less leverage over them.
Some diplomats worry that the Cypriot strategy is to "Europeanise" the Cyprus dispute, moving the dispute away from a UN framework where compromise is inevitable.
Meanwhile, diplomats are searching for possible moves on northern Cyprus that could encourage the Turks to open their ports.
Last month, the EU did finally agree 139m euros ($166m) of aid for the north that the Greek Cypriots had been blocking.
But the Turkish Cypriots and Turkey itself also want to see northern Cyprus allowed to trade directly with the EU, something the Greek Cypriots consider tantamount to sovereignty for the north. So it is stalemate.
Some wonder quietly if the threat of formal recognition of the north could push the Greek Cypriot side back to the negotiating table.
Others hope the Greek Cypriots will not push the negotiations over the brink this autumn, through pure self-interest - since once negotiations stall, their leverage over Turkey is gone.
But cool heads will need to prevail on all sides, if a way through is to be found in the months ahead.
Kirsty Hughes is a former senior fellow of the Centre for European Policy Studies, Brussels.