As cyclone 'Amphan' nears theshores of West Bengal, the Kolkata Port Trust (KoPT) has issued warnings to mariners and stopped movement of all vessels to and from its docks to prevent any damage to port assets and merchant ships, an official said on Tuesday.The port authority has also asked ships anchored at the sandheads to take necessary measures to avoid any accident due to the storm, he said."Control rooms have been set up at Subhas Bhavan, Sagar and Jawahar Tower at Haldia for 24-hour monitoring. All 19 vessels at sandheads have proceeded to deep sea to avoid the path of the storm," KoPT chairman Vinit Kumar said.All cargo handling operation at Diamond Harbour and Sagar anchorage has also been stopped, he said."All the movement of inward and outward vessels have been cancelled at Kolkata and Haldia docks as a safety measure to prevent any damage to port assets and merchants' vessels," the official said.The vessel management system will not be functioned during the storm to prevent it from lightning strikes, he said.The barges have been asked to take adequate protection and no ships have been kept at the oil jetties of Haldia and Budge Budge, KoPT spokesperson Sanjoy Kumar Mukherjee said.At present, there are 15 merchant vessels at Kolkata Dock System (KDS) and 11 at Haldia Dock Complex (HDC)."Pilot vessel Ma Ganga and four pilot launches have been given shelter inside the Haldia Dock Complex as a precautionary measure," he said, adding that all ships berthed at the HDC and the KDS have been directed to take necessary steps with additional mooring ropes.All the utility crafts, either owned by the port or hired, have been taken inside the docks except few boats which will be deployed for exigency," he added.