A holdout is someone who refuses to agree or act with other people in a particular situation and by doing so stops the situation from progressing or being resolved. France has been the holdout in trying to negotiate an end to the dispute
the act of hiding playing cards in a gambling game so they are available for personal use later a refusal by a negotiator to come to terms in the hope of obtaining a better deal a negotiator who hopes to gain concessions by refusing to come to terms; "their star pitcher was a holdout for six weeks