European governments delayed their imposition of environmental proposals for international aviation and may wait for international agreements to be in place before imposing European standards on international flights. Europeans set 2012 for imposition of rules on international aviation flying into Europe, then advanced it to 2011 and now has moved it back to 2012. U.S. airlines charge that unilaterally imposed regulations would violate international law. The New York Times reported João Vieira of Transport and Environment, an advocacy group based in Brussels that focuses on sustainable transportation, said the aviation rules as revised would let the airlines pollute 90 percent more than in 1990, even as other European industries are making progress toward lowering their emissions from 1990 levels. But aviation interests would argue that is only fair since aviation has cut green house gas emissions by 70 percent over the last three decades, while other industries have largely stood still. European airlines also argue that failure to modernize air traffic control systems increases emissions as airlines are forced into circuitous routings and holding patterns. Airlines say they should not be responsible for such excess emissions and any regulations should come under rules set by the International Civil Aviation Organization rather than as a piecemeal regional approach. The Times reported that European Union ministers proposed airlines buy 10 percent of permits via an auction rather than the 25 percent proposed by the European Parliament. The rest would be distributed free. European governments have set a final agreement for publication at the end of the year.