DCM said this month it was seeking to buy smaller rival Shimachu at 4,200 yen ($39.74) a share for a total 164 billion yen.

Shimachu, whose shares closed at 4,195 yen on Tuesday, has said it supports DCM's bid. This would make any bid by Nitori hostile, Nikkei reported.

The tender offer started on Oct. 5 and was to run until Nov. 16.

All three companies could not be reached for comment outside business hours.

($1 = 105.6800 yen)

(Reporting by Chang-Ran Kim; Editing by Edmund Blair)