This is the heartwarming moment a loyal pet dog stayed by its owner's side when he collapsed on the street.

The elderly man reportedly stumbled and fell unconscious outside his home in Roi Et, Thailand.

After receiving the report, paramedics from the Nakhon Saket Emergency Rescue Unit quickly arrived at the scene on June 6.

When rescuers reached the house, they found the black dog guarding the man, who was lying motionless on the pavement.

Footage shows the emergency team surrounding the victim as he regained consciousness, with the alert pooch standing protectively in front of him.

Fearing the dog might become aggressive, the medics kept their distance until the pensioner calmed the animal down, allowing them to administer first aid.

The man then sat up as rescuers examined a wound on his head.

Local media reported that he did not sustain any serious injuries from the fall.

The elderly man reportedly lives alone with two male dogs and has no relatives.