VIENNA, June 21 (Reuters) - A technical fault in air traffic control, triggered by security measures for peace talks between the U.S. and Iran in Switzerland, caused disruptions at Zurich airport on Sunday, aviation authorities said, adding the problem had been resolved. The glitch occurred following the integration of a restricted zone over Buergenstock, the Swiss mountain resort where negotiations are taking place, into radar display systems, Swiss air traffic control authority Skyguide said.