Hitachi Ltd.'s chief executive officer said he's open to deeper ties, which could include merger talks, with Mitsubishi Heavy Industries Ltd., after the equipment makers failed in their bid for Alstom SA's power business.

"We've built a relationship with them to talk frankly" about extended partnerships, Hiroaki Nakanishi said in an interview at a business forum Thursday in Tokyo. "The possibility of merger discussions shouldn't be denied."

While the companies are in talks about possible ties outside their thermal-power equipment businesses, they've yet to come up with candidates among their other operations, he said.