历久弥坚｜lì jiǔ mí jiān

Meaning: to become more resolute with the passing of time

Original: “双方践行世代友好理念，传统友谊历久弥坚。双方隆重纪念《中俄睦邻友好合作条约》签署20周年，我同普京总统宣布《条约》延期并赋予其新的时代内涵。“