By Zohar Blumenkrantz Transportation Minister Ephraim Sneh threatened to take three regional routes from national airline El Al unless it submits a new schedule within three months to increase the frequency of service. The destinations are Athens (El Al currently flies there four times a week), Istanbul (two) and Larnaca. Sneh's threat follows the transportation ministry's investigation into several routes where the state-owned airline runs relatively few flights. Meanwhile, Arkia and Israir are suing the state to recognize their status as national carriers alongside El Al. El Al commented yesterday: "A month ago El Al announced that it was considering increasing the frequency of these flights within the regional network following a recent investigation that revealed the potential of these activities. No progress on Russian aviation spat No progress was made in a four-hour meeting yesterday between Sneh and Russian Aviation Minister Tatiana Anudina on a dispute over charter flights. Russia has refused to allow both Sun D'Or, El Al's charter subsidiary, and Israir to run flights to Moscow, and Israel recently won High Court backing to withdraw its route license for Russia Airlines from August 14. (Whether it will actually do so is not yet clear). A Ministry spokesman said talks would continue.