How does romeo react when Tybalt and mercutio start fighting?

When Romeo sees Tybalt and Mercutio beginning to fight, he takes action to try to stop them. He steps between them and pushes Tybalt away, urging him to calm down and not to fight. He tells Tybalt that he has "no quarrel" with him and that they are both family. He also tries to reason with Mercutio, urging him not to fight and not to draw his weapon. However, despite Romeo's efforts, the fight between Tybalt and Mercutio continues.