Rihanna's lawyer said Los Angeles prosecutors are expected to call the pop star to testify at singer Chris Brown's court hearing next month.

Brown, 20, was arrested and charged with assaulting Rihanna, his 21-year-old girlfriend, in February during a heated argument in a car.

He has pleaded innocent to the charges and his next court hearing is June 22, EW.com said.

"The D.A. has advised me that she will be subpoenaed (to testify,)" Rihanna attorney Donald Etra told People.com. "She absolutely will comply."