Switzerland and Germany have failed to finalise an accord aimed at ending a long-running dispute over noise pollution out of Zurich airport. In the eleventh and final round of negotiations, the two countries reached only a partial agreement on ways to settle the details of a deal which was struck in April.
As a result, the remaining controversial issues must now be re-examined by Switzerland's transport minister, Moritz Leuenberger, and his German counterpart, Kurt Bodewig.
During the latest negotiations, Germany insisted that once the number of flights was reduced, there should be no means of turning back.
However, Swiss negotiators rejected this demand. They argued that Zurich airport would not be able to deal with an unexpected increase in traffic during the planned 41-month transition period.
Under the deal struck in April, flights over southern Germany are to be reduced by 35 per cent, from the current figure of 150,000 down to 100,000.
Differences also remained over compensation payments to German communes which have been complaining about noise and environmental pollution. Furthermore, no consensus was reached on a timetable for a gradual reduction in the number of flights over German territory by the year 2005.
Switzerland did however agree to create waiting zones for planes in its own airspace. No details concerning these zones were available yet.
Based on the agreement, waiting zones in German airspace would have to be situated above 1,800 metres during the day, and above 4,000 metres at night.
Planes not transiting in a waiting zone would be banned from using German airspace between 22.00 and 06.00. A reduction in flights on weekends and bank holidays would also be phased in by autumn 2002.
swissinfo with agencies