Greece and Turkey are both NATO, but they never gotten along very well. Apparently, they have been playing bumper boats and this 12 February 2018 incident is not the first time. The Turkish cutter is larger. We looked at her class earlier.  The Greek vessel was a Damen Stan Patrol 5509 (55 meters long and 9 metes of beam) offshore patrol vessel, which reportedly suffered significant damage to her hull. Here is a page that provides info on both classes,