A US firefighter has been praised for giving a dog 20 minutes of "mouth-to-snout" resuscitation after the animal was rescued from a house fire.

The dog was overcome by the heat and smoke of the blaze in Santa Monica, California, and was unresponsive.

But firefighter Andrew Klein managed to bring 10-year-old Nalu, a Bichon Frise/Shih Tzu, "back from the dead".

Mr Klein discovered Nalu unconscious in a back bedroom after crawling on all fours into the blazing apartment

"He was totally lifeless," the firefighter told the Associated Press news agency. "I picked him up and ran out of the apartment because time is key, especially with a small dog… Failure was not an option.''

Nalu was also given oxygen and is now fully recovered

As the dog's distraught owner Crystal Lamirande knelt crying nearby, Mr Klein and his crew spent the next 20 minutes giving the dog oxygen and performing "mouth-to-snout" resuscitation.

"After 20 minutes, the dog began breathing on its own and regained consciousness, even regaining the ability to walk around," the Santa Monica Fire Department said in a press release.

Nalu has now fully recovered after spending 24 hours in an oxygen tent.

Ms Lamirande, a radiology nurse, said she was overwhelmed by the effort made by Mr Klein and his team to save her dog.

"His eyes were glazed over and he was not breathing and I assumed he was dead," she said. "But the firefighter said 'I'm a positive person. Let's just get him back'."