NATO Secretary General Jens Stoltenberg (C) addresses a session of the Ukrainian Parliament in Kiev, Ukraine, on October 31, 2019. (Photo: Sergey Starostenko/Xinhua)

Addressing the Ukrainian Parliament, Stoltenberg said as a sovereign state, Ukraine has the right to choose its security systems. NATO membership is the decision of the members of the NATO alliance and those who would join it.

He stressed that NATO advisers will help Ukraine implement Euro-Atlantic principles and best practices to strengthen the rule of law, ensure minority rights, and fight corruption.