Paralympic champion Oscar Pistorius has told the High Court in Pretoria that he never intended to pull the trigger when he shot his girlfriend Reeva Steenkamp dead.

The 27-year-old denies murder by maintaining that he mistook the South African model for an intruder when he fired the gunshots through a bathroom door at his home in Pretoria on Valentine's Day last year.

While being questioned by prosecutor Gerrie Nel, Pistorius told the court that he didn't have time to think before pulling the trigger, but claimed that he never had the intention to shoot.

The double amputee claimed that the noise that he heard coming from the bathroom caused him to fire the gun, and when Nel said that if he had waited a second he would not have pulled the trigger, Pistorius said: "That's a possibility."

Earlier in Thursday's proceedings, Pistorius insisted that he did not treat Steenkamp "badly" during their relationship.