Fishermen were amazed when a calm whale shark swam over to their boat to be stroked on its back.

The endangered sea creature floated to the vessel of the coast of Phetchaburi, the western Thailand, on July 8.

Thepthai Phupiwmek recorded his colleagues gently pat the whale before it disappeared into the depths off the coast of Cha-am.

Thepthai, who is heard talking to a whale, said it has not seen a whale shark before. They believe that touching a whale shark will bring them luck.

He says in the video: "Come here my friend, let me touch you a little bit for good luck. It is so great to see you today."

Whale sharks, or Rhincodon Typus, are the largest harmless fish in the world and grow up to 40ft long.

They are classified as 'endangered' on the International Union for Conservation of Nature (IUCN) Red List of Threatened Species.