Senior Saudi Islamic scholar Sheikh Saleh Al-Fawzan said in a lecture posted on February 22, 2018 on Min Aqwal Al-Ulama on YouTube that Muslim men have the right to keep women as concubines and have sex with them. He explained, that while Islam forbids having sex with a married woman, if she is a war captive, she is in the possession of the Muslim and he is permitted to keep her as a concubine, because her marriage contract to an infidel is annulled.
Sheikh Saleh Al-Fawzan: "The Muslims captured women in the  Battle of Awtas.
"They took from the [infidels] money and women as booty. The Companions of the Prophet Muhammad became confused. It was customary for the owners of women captured at war to take them as concubines. They have the right to take them as concubines and have sex with them, by virtue of possessing them. The possession of a captured woman outweighs her marriage contract. It allows the master to have sex with the woman he owns. This is called concubinage.
"But the Prophet's Companions were confused, because Allah has made married women haram, and these women had infidel husbands. So Allah sent down the verse 'married women except those you possess.' When a woman is taken captive, her marriage contract to her [infidel] husband is annulled. If she is taken captive, she becomes property of the Muslims, and the infidel's marriage contract with her is annulled. She becomes the property of the Muslim, and he can take her as a concubine."