An Italian diver has captured the moment he swam with a huge whale shark during a spearfishing day in the Persian Gulf. <br /><br />In remarkable footage, Federico Erroi says that he saw a huge shadow 20 metres beneath the surface of the water on his way back to his boat and immediately dived towards it.<br /><br />For a brief moment he swims alongside the whale, holding its fin.<br /><br />"When my eyes saw the huge whale shark, my heart started pounding," Erroi explains. "It was like a dream: me and a whale shark swimming together in the silence of the Persian Gulf."<br /><br />On his YouTube channel, Erroi describes the moment further: "My heart is pumping, my hands starts to shake, eyes full of joy, in front of one of the giant animals in the world. <br /><br />"We danced together in the silent world, no words can explain every single emotion felt in that few seconds when my hand grabbed ... his fin."<br /><br />The whale shark is the largest fish in the sea and is classified as an endangered species. <br /><br />Experts have said that while it is fun to swim with whale sharks, it is not recommended that divers catch rides by hanging onto their fins.