The fight was originally scheduled for 31 May in Oberhausen, but was postponed because Chagaev has a viral infection.
Universum promotions said Wednesday the venue for the rescheduled fight had not been decided.
The unbeaten Chagaev (24 wins with 1 draw) won a majority decision against Valuev in April 2007. Valuev (48-1) won a lopsided decision against former WBO champion Sergei Liakhovich in February.
