Uncompromising

Un-com′pro-miˊsing

,

Adj.

Not admitting of compromise; making no truce or concessions; obstinate; unyielding; inflexible.

–

Un-com′pro-miˊsing-ly

,

adv.

,

Adj.

s as z. Not compromising; not agreeing to terms; not complying.

uncompromising ‎(comparative more uncompromising, superlative most uncompromising)

Inflexible and unwilling to negotiate or make concessions.
- 1959, Georgette Heyer, chapter 1, in The Unknown Ajax:
  But Richmond, his grandfather's darling, after one thoughtful glance cast under his lashes at that uncompromising countenance appeared to lose himself in his own reflections.
- 2014 November 14, Stephen Halliday, “Scotland 1-0 Republic of Ireland: Maloney the hero”, in The Scotsman:
  The visitors, who surprisingly dropped their talismanic record goalscorer Robbie Keane from their starting line-up for a competitive game for the first time in 13 years, adopted a direct and uncompromising approach.
Principled.

inflexible and unwilling to negotiate or make concessions

principled