WASHINGTON (AP) - American activists are urging European trade negotiators not to weaken environmental and food standards as they begin talks in Washington on a trans-Atlantic free trade agreement.

About 50 activist groups were allowed to make brief presentations on Wednesday to trade negotiators and the media, expressing their views on aspects of the trade agreement. They included environmental groups such as the Sierra Club, labor representatives like the AFL-CIO and a range of food, agricultural, business and intellectual property interests.

Some of the speakers particularly praised Europe's approach to product safety, regulation of chemicals and strict limitations on genetically modified food - which is expected to be one of the more contentious subjects in the negotiations.