Nissan and Honda ended merger talks to forge a $60 billion car company on Thursday, pitching Nissan deeper into uncertainty and highlighting the pressure on legacy automakers from Chinese rivals upending the industry.

The Japanese companies’ decision to call off negotiations highlights the challenges legacy automakers face in partnering to tackle new technologies.

Honda and Nissan announced Thursday they were terminating negotiations for a mega-merger that would have created the world's third-largest car company.