Germany's parliament has rejected a controversial aviation agreement with Switzerland, two days after the Swiss parliament voted it down.
The German Upper House of Parliament, the Bundesrat, on Friday refused to ratify the air transport accord, aimed at ending a long-running dispute over noise pollution.
Representatives of the opposition Christian Democratic Union said the treaty conceded too much ground to Switzerland and put the main burden on the population of southern Germany.
Residents have complained for years about noise pollution out of Switzerland's main airport of Zurich, which lies less than 20 kilometres from the border with Germany.
The opposition called on Chancellor Gerhard Schröder's government to seek fresh negotiations with Switzerland. For its part, the German government insisted that the treaty was a fair compromise.
Observers say the ruling coalition will override the Bundesrat's decision.
Controversy in Switzerland
On Thursday, Switzerland's House of Representatives rejected the aviation deal on the grounds that it discriminated against the Swiss.
A majority argued that the deal jeopardised the future of Zurich airport and did not conform to European Union regulations.
But the decision cannot take effect unless the Swiss Senate confirms it later this year.
Germany has threatened to unilaterally impose strict measures, if Switzerland refuses to ratify the air transport agreement struck by the transport ministers of both countries last October.
The accord foresees cutting by a third the number of flights allowed to use airspace over southern Germany before landing at Zurich airport. This would mean a reduction from 150,000 to 100,000 a year. It also includes a ban on night flights and weekends.
swissinfo with agencies