The US has urged the European Union to speed up its process for approving new genetically modified (GM) products.
Genetically modified crops have been grown in the US for years
The call came after the World Trade Organisation publicly released its ruling that the EU acted illegally in banning GM imports from 1999 to 2004.
The case was instigated by the US, Canada and Argentina who were critical of an EU moratorium on GM food crops.
EU officials said the ruling had little impact because the moratorium had already been lifted.
Since the case was first brought to the WTO in 2003, the EU has given decisions on 10 GM product applications and is reviewing more than 30 others.
"This confirms that the EU system for GM approval authorisation has functioned in strict application of the law," said Peter Power, spokesman for the EU Trade Commissioner Peter Mandelson.
GM crops have drawn protests in France and around the EU
However, US Trade Representative Susan Schwab said the EU was still operating a partial moratorium on GM imports, based on political rather than scientific criteria.
"Although the EU approved a handful of biotech applications following the initiation of the case in 2003, the EU has yet to lift the moratorium in its entirety," Ms Schwab said in a statement.
"Some biotech product applications have been pending for 10 years or more and applications for many commercially important products continue to face unjustified, politically motivated delays."
The WTO also challenged six EU members - Austria, Belgium, France, Germany, Italy and Luxembourg - for independently banning GM crops that had already been approved by the EU.
The 1,000-page WTO ruling confirmed a preliminary verdict that was issued in February, and was released to the countries involved in the dispute in May.
It did not address the issue of whether GM crops were safe or if they could be compared to naturally occurring products.
Crops including corn or soybeans that have been genetically modified to resist insects or disease have been widely grown in the US for years.
In August the EU introduced emergency measures to ban imports of US rice that had been contaminated with an unauthorised genetically modified variety.
The GM variety was later found in packets of own-brand rice sold by a UK supermarket.