This is the amusing moment a pet dog was hilariously confused by a helium balloon tied to its back.

Rhea Pahilga and her boyfriend had a picnic at a park when they decided to buy a dinosaur balloon for their dog, Cooper, a four-year-old Shih Tzu in Manila, the Philippines, on February 9.

Footage shows Cooper walking in the field with Rhea when he saw a floating dinosaur balloon following him.

He was startled when the balloon hit the grass, causing him to run away.

After realizing that it wouldn't harm him, he continued to walk as if nothing had happened.

Rhea said: 'At first, he didn't see the balloon attached to his clothes, and when we went back to our picnic place, he drank a lot of water.'

Rhea celebrated his birthday along with his partner and dog. Her partner insisted on buying the balloon to match the pooch's dino cloth.