A heated row has kicked off between the USA and European authorities over import tariffs.
The US has lodged a complaint with the World Trade Organisation over import charges on computer screens and other technology products coming into Europe.
Tech companies, among them Hewlett-Packard, have accused the EU of violating both "the spirit and the letter" of the WTO's 1997 Information Technology Agreement (ITA).
This axes tariffs on an array of high-tec products to encourage trade.
"The EU should be working with the United States to promote new technologies, not finding protectionist gimmicks to apply new duties to these products", said Trade Representative Susan Schwab.
"Therefore, we urge the EU to eliminate permanently the new duties and to cease manipulating tariffs to discourage technological innovation", she said in a statement.
The exports are alleged to be worth more than $70 billion.
But the EC has blown out the complaint and argued that Washington has ignored its requests to renegotiate which products are covered by the ITA deal.
"The ITA has a review clause which can be invoked by members at any time. The EU has said it is willing to negotiate with all other ITA members. The US is not willing to do this. Why not?" the EC said in a statement.