This is the gruesome moment a tree snake was seen swallowing an entire gecko.

The green reptile pounced on the tokay gecko while it was slithering through the home in Nakhon Ratchasima, north eastern Thailand on June 6.

Wisansiri Monklang recorded the wild snake after it had pounced on the reptile and wrapped its jaws around its head.

Close-up footage shows the reptile slowly gulping down the lizard, which leaves a large lump in the snake's body.

Wisansiri said he was walking out of his place for lunch when he spotted the tussle on the ground near his motorcycle.

He said: "It was amazing that I had a chance to see a reptile killing another. I had never seen a snake fitting a its prey into its mouth like this before."

Golden tree snakes are found throughout Southeast Asia where they feed on lizards, rodents and other small prey.