The EU delegation at the talks is led by German Foreign Minister Frank-Walter Steinmeier, whose country holds the EU presidency, and Olli Rehn, EU commissioner for enlargement, while the Turkish delegation is headed by Economic Minister Ali Babacan.
The two sides opened talks on statistics and financial control, but France vetoed negotiations on economic and monetary policy.
"We are not satisfied with the technical explanations provided to us so far and hope that [better] progress will be achieved during Portugal's EU presidency," Babacan said.
Even before he won presidential elections in France, Nicolas Sarkozy stated he opposed Turkey's EU membership, because it belongs "not in the European Union but a Mediterranean Union."
The EU-Turkey negotiating process, which started in October 2005, comprises 35 policy areas or chapters. Experts say membership talks could take anywhere between 10 and 15 years.