WASHINGTON, May 1 (Reuters) - European regulators want the United States to ease restrictions on foreign investment in U.S. airlines, and will press hard for that change if a court ruling forces an overhaul of American and European "open skies" deals, a top European Union official said on Wednesday. Loyola de Palacio, EU vice president for energy and transportation, told reporters at a news conference that rules limiting non-U.S. companies to no more than 25 percent of voting stock in U.S. domestic carriers would be the top priority in any transatlantic aviation talks. De Palacio met with Deputy Transportation Secretary Michael Jackson on Wednesday to review European aviation issues, including war-risk insurance, post Sept. 11 security measures, and the future of U.S. "open skies" treaties with eight EU countries. The European Union's highest court, the European Court of Justice, is widely expected to rule soon on a petition that seeks to declare those accords illegal and grant sole negotiating rights to the European governing bloc. De Palacio signaled that the European Union is ready to negotiate on behalf of its 15-member nations. "The American administration is well aware that a the court outcome will mean that a decision has to be made," de Palacio said. "I can't say what they (Bush administration officials) are going to do. I think they are considering the possibility of not only negotiating 'open skies' but maybe going a bit forward." Proponents of relaxing foreign ownership rules argue that it would help domestic airlines at a time when they are struggling to reverse staggering losses linked to a steep decline in travel due to Sept. 11 and recession. The Transportation Department has not ruled out changing the ownership rule but no proposals are in place. ©2002 Reuters Limited.