The Collaborative International Dictionary of English v.0.48:

Reassert \Re`as*sert"\ (r[=e]`[a^]s*s[~e]rt"), v. t.
   To assert again or anew; to maintain after an omission to do
   so.
   [1913 Webster]

         Let us hope . . . we may have a body of authors who
         will reassert our claim to respectability in
         literature.                              --Walsh.
   [1913 Webster]

WordNet (r) 3.0 (2006):

reassert
    v 1: strengthen or make more firm; "The witnesses confirmed the
         victim's account" [syn: confirm, reassert]