Striker Dalla Valle, 18, has been on the books at Anfield since January 2008 but the Finland U-19 international has failed to break into the first-team squad.
Swedish left winger Alex Kacaniklic, meanwhile, arrived at Liverpool from Helsingborg in the summer of 2007 and has been fighting it out in the reserves.
Cottagers boss Mark Hughes has targeted the youngsters as possible stars for the future, and former Fulham boss Roy Hodgson has allowed them to leave Anfield.