Not making concessions:
— Took an uncompromising stance in the peace talks.
— Uncompromising honesty.

synonyms: inflexible, sturdy.

Roget 739: severe; strict, hard, harsh, dour, rigid, stiff, stern, rigorous, uncompromising, exacting, exigent, exigeant^†, inexorable, inflexible, obdurate, austere, hard-headed, hard-nosed, hard-shell [U.S.], relentless, Spartan, Draconian, stringent, strait-laced, searching, unsparing, iron-handed, peremptory, absolute, positive, arbitrary, imperative; coercive etc. 744; tyrannical, extortionate, grinding, withering, oppressive, inquisitorial; inclement etc. (ruthless) 914.1; cruel etc. (malevolent) 907; haughty, arrogant etc. 885; precisian^†.    ... show more

Roget 82: conformable to rule; regular etc. 136; according to regulation, according to rule, according to Hoyle, according to Cocker, according to Gunter; en regle [Fr.], selon les regles [Fr.], well regulated, orderly; symmetric etc. 242.    conventional etc. (customary) 613; of daily occurrence, of everyday occurrence; in the natural order of things; ordinary, common, habitual, usual, everyday, workaday.    in the order of the day; naturalized.    typical, normal, nominal, formal; canonical, orthodox, sound, strict, rigid, positive, uncompromising, Procrustean.    secundum artem [Lat.], shipshape, technical.    exempIe [Fr.].    illustrative, in point.    ... show more

Dutch: compromisloos
Polish: bezkompromisowy