Robert Pattinson and Kristen Stewart's reunion at the MTV Video Music Awards "could be a real embarrassment."

The Twilight stars are experiencing turmoil in their real life romance as Kristen recently confessed to cheating on Robert with Rupert Sanders.

The pair are slated to present an award together at the ceremony that will take place just weeks from now.

"This event could be a real embarrassment," a source told British newspaper The Mirror. "The idea was for them to jointly present awards but that is looking unlikely now. If they go up on stage at the same time fans will believe they are united again. If Kristen goes up alone the crowd reaction will be astonishing. Fans have bought into the romance on and off screen so she could be in for a horrible night."

Producers are also reportedly concerned with how they will host both Kristen and Robert at the same time.

"It will be tricky for them to keep apart on the red carpet, backstage and the afterparties," the insider explained.

The MTV Video Music Awards hosted by comedian Kevin Hart will take place on September 6 in Los Angeles.