Plans to extend the mandate of the Swiss peacekeeping mission in Kosovo until the end of 2020, while reducing the size of the force has won initial approval from parliament.
The Senate clearly endorsed a government proposal for a three-year extension and gradually limiting the troops to 165 members from 235.
The other parliamentary chamber, the House of Representatives, still has to discuss the bill.
Most speakers on Monday stressed the importance of the NATO-led international peacekeepers to stabilise the Balkan region which split off from Serbia.
Defence Minister Guy Parmelin said the Swiss troops played an essential role in transport and engineering for the international mission. Stability and security in southeastern Europe were also in Switzerland own interest.
Switzerland hosts one of the biggest Kosovo expat communities in Europe since the conflict erupted nearly 20 years ago.
Critics argue the mission is too costly and counterproductive.
Neutral Switzerland has been taking part in the KFOR mission since 1999 It has also been participating in missions in Bosnia-Herzegovina.