President François Hollande vowed Tuesday to defend French labels such as Champagne or Roquefort cheese in any future
US-European Union trade pact.

Underscoring his reticence to rush into a deal, Hollande said an agreement would have to protect the geographical names that are the source of many of France's best known agricultural exports.

“There can be no question of sacrificing our interests to get a deal. Our labels are our heritage,” said the French leader, who has already promised to protect his country's farming sector in any deal.

The European Union and United States are thrashing out plans for a vast free-trade zone, unifying rules and slashing tariffs to create a combinedmarket of 850 million people.

President Barack Obama has pressed for the Transatlantic Trade and Investment Partnership to be agreed by the end of the year.

But support for the accord on both sides of the Atlantic appears to be diminishing.

Many activists and professional organisations have lined up against provisions of the pact ranging from food safety to environmental protection, intellectual property rights, the protection of farmers, or the sovereignty of governmental decisions.

One key point in negotiations is the European system of protecting geographically-based product names such as France's Champagne, Roquefort and Camembert or Italy's Gorgonzola cheese.

The United States does not recognise the system, relying instead on trademarks to provide brand protection.

US Trade Representative Michael Froman, speaking in Stockholm, said he was holding out for a deal that satisfied all parties.

“We in the United States very much value European products, French products, and we want to make sure that they have an opportunity to have access to our markets as we want to have access to European markets,” he told a joint news conference with EU trade chief Cecilia Malmstroem.

Malmstroem said the negotiations were difficult, but there was still hope for a deal.

“We think there is still a chance, and we are working in that direction, to do everything we can to achieve this agreement before the end of the year. It is difficult, but it is what we strive for,” she said.