The audio, along with a photo of the suicide bomber identified as Abu Sinan al-Najdi, was posted late yesterday on IS-affiliated Twitter accounts.
The speaker on the recording vowed more attacks, saying Saudi rulers and troops "will not enjoy peace" for taking part in the US-led coalition battling IS in Iraq and Syria. He urged other militants to carry out suicide bombings, saying explosive belts are more effective than firearms.
The attack in Abha on Thursday was one of the deadliest against Saudi Arabia's security personnel in years. Most of the victims were members and recruits of the kingdom's special forces.