Lesotho Prime Minister Thomas Thabane on Thursday announced on state radio that he will step down on July 31 amid mounting pressure for him to resign over the murder scandal involving his current wife, Maesaiah.

Thabane's announcement came just hours after police said that the 80-year-old premier will likely be charged on Friday with the murder of his former wife, Lipolelo.

"The prime minister is going to be charged with the murder. The police are preparing directives and he will probably be charged tomorrow," Reuters quoted Deputy Police Commissioner Paseka Mokete as saying.

Mokete added that the fact that Thabane will be charged did not necessarily mean he was there but that he was acting in common purpose.

Police had already questioned Thabane after his mobile phone was connected to communication records from the scene of the killing of Lipolelo Thabane.

Lipolelo was killed two days before the Prime Minister’s inauguration for a second term, and two years after a court ruled that the deceased was the lawful first lady and entitled to benefits.

Thabane and Maesaiah were married two months after Lipolelo was shot dead by an unknown assailant near her home in Maseru. Thabane and Lipolelo were in the middle of a bitter divorce and her killing was suspected to be a political assassination.

Maesaiah was also charged with the attempted murder of Thato Sibolla, a friend of Lipolelo who was wounded at the scene.

Maesaiah will stand trial on March 17, according to a ruling by a magistrate when she appeared in court on Tuesday. She has denied any involvement in the murder but cannot enter a plea until the trial begins.