TOKYO, April 21 (Reuters) - China's security agreement with the Solomon Islands may have an impact on security for the region and is a likely topic for discussions between the leaders of Japan and New Zealand later on Thursday, Japan's chief cabinet secretary said.

"This agreement is likely to have an impact on the overall region's security, so we are watching it with concern," Hirokazu Matsuno told a news conference. (Reporting by Elaine Lies; Editing by Tom Hogue)