(reuters) -- Swiss officials visited an airfield in the Golan Heights region on three occasions in 2012, 2013 and 2015 to monitor tests of the Israeli-built Hermes 900 aircraft that they are buying for $265 million.

The visits, which lasted several days, took place in an area which Switzerland does not recognise as being part of Israel, which took the land from Syria following a 1967 war.

Following an internal review this year, the Swiss found the presence of their personnel at the airfield contradicted the Swiss position on the Middle East conflict, the ministry said.

The visits took place without the knowledge of the Swiss foreign ministry. No further visits have taken place since the affair came to light, it said in a statement.

"This incident was a communication breakdown," it said. "Those who were informed about the activities did not realise Swiss officials were not allowed to be there and those who knew about the restrictions were not informed about the planned activities."

Future tests will now take place at an airfield within Israel, it added, with the drones due to enter service in 2020.

Switzerland has frequently acted as a broker in the Middle East, most recently hosting peace talks about the war in Syria in Geneva and carrying out consular services for Iran and Saudi Arabia in their respective countries.

"This case damages the credibility of Switzerland with regards to all governments in the region which are in conflict with Israel," veteran diplomat Tim Guldimann, a lawmaker from the Social Democrat party, told the Tages-Anzeiger paper.
 

(Photo: swissinfo)