DUBAI, Oct 10 (Reuters) - Gulf states are lobbying Washington to stop Israel from attacking Iran's oil sites because they are concerned their own oil facilities could come under fire from Tehran's proxies if the conflict escalates, three Gulf sources told Reuters. As part of their attempts to avoid being caught in the crossfire, Gulf states including Saudi Arabia, the United Arab Emirates and Qatar are also refusing to let Israel fly over their airspace for any attack on Iran and have conveyed this to Washington, the three sources close to government circles said.