The Union Minister of shipping GK Vasan said that his Ministry is taking further steps to provide the state of the art aids to facilitate navigation and to set up a most formidable surveillance network for identifying unfriendly vessels.    The Minister was speaking after laying the foundation of the Parangipettai Navtex Transmitting Station at a function in Chennai recently.    The Minister said that as part of the government's obligations under the Safety of Life at Sea Convention, his Ministry has asked its technical arm of the Directorate General of Lighthouses & Lightships (DGLL) to provide for continuous Navigational Telex (Navtex) coverage of Indian waters.    DGLL has made a meticulous plan in covering the entire Indian Coastline including islands by establishing seven transmitting stations where safety, weather, and search and rescue related broadcast will be made up to 250 Nautical Miles.