Jason Derulo and Jordin Sparks are still fighting infidelity rumors, weeks after ending their relationship.

Star Magazine reported that a 30-year-old model named Carmen Ortega claimed she had an affair with the 25-year-old "Talk Dirty" singer while he was still dating Sparks. Ortega said the two met through mutual friends at an L.A. recording studio and become romantically involved. During their alleged fling, Ortega said she thought the singer was single.

"We dated for a month," Ortega revealed. "We went out in public with friends a few times, so I assumed he didn't have a girlfriend."

Ortega, who has been linked to several A-list celebrities including LeBron James and Reggie Bush, said she "cut ties with Derulo immediately" after learning about his relationship with Sparks. 

"He tried telling me their relationship was strictly fueled by management teams. He lied to me the entire time," she added.

The singer recently released a statement denying any rumors of infidelity.

"I spent three great years with Jordin and she is one of the most amazing people that I have ever met," he said. "But as in all relationships, there are ups and downs, and at this time we have decided to amicably part.

"Infidelity, cheating or deceit played no part in our relationship or our break-up, and I hope that people respect our privacy as we move forward with our lives. Though I think it is a private matter and intended to keep my break-up Jordin personal, due to bogus and irresponsible lies being reported by insensitive media outlets, it became necessary for me to comment."