Washington will "intensify" talks with the EU to resolve a longstanding fight on aerospace subsidies following a WTO ruling criticizing US aid for Boeing, an American trade official said Tuesday. "The United States is determined to find a resolution to this dispute," US Trade Representative Robert Lighthizer said. "We are waiting for a response from the EU to a recent US proposal and will intensify our ongoing negotiations with the EU to restore fair competition and a level playing field to this sector." Lighthizer said a ruling clearing the way for $4 billion in EU tariffs on American goods had "no valid basis." jmb/cs