ZURICH, Feb 10 (Reuters) - Switzerland has rejected a request from Spain to allow it to re-export Swiss-made anti-aircraft guns to Ukraine, the Bern government said on Friday. Madrid had made the request in January to allow two 35mm anti-aircraft guns, which were made in Switzerland, be sent to Ukraine. Madrid had made the request in January to allow two 35mm anti-aircraft guns, which were made in Switzerland, be sent to Ukraine