Ukrainian President Petro Poroshenko has said that staying out of the NATO military alliance was a "criminal" policy that his government is ready to reverse.
Speaking on September 22 while chairing a meeting of Ukraine's Security Council, Poroshenko also said it will be up to a popular vote to decide on membership.
NATO Secretary-General Jens Stoltenberg was in attendance at the meeting in Kyiv.
NATO officials have said that Ukraine must carry out political, economic, and military reforms before the country can even be considered for membership.
Stoltenberg told the meeting that "Ukraine can rely on NATO" and that "NATO provides Ukraine with political and practical support."
Meanwhile, Kremlin spokesman Dmitry Peskov warned that any NATO expansion toward Russia’s borders “will make us take relevant countermeasures to ensure our own security."
Ukraine has been fighting with separatist rebels in the east since April 2014 in a conflict that has resulted in the deaths of more than 7,900 people.
Kyiv and Western governments accuse Moscow of directly backing the rebels, something the Kremlin denies.