rejectionist
noun
[ rɪˈdʒɛkʃ(ə)nɪst ]
• a person who rejects a proposed policy, in particular a supporter of Palestinian independence who rejects the possibility of a negotiated peace with Israel.
• "the rejectionists want the agreement to fail at all costs"
rejectionist
adjective
• rejecting a proposed policy.
• "rejectionist groups"