(NewsNation) — Ukrainian Prime Minister Denys Shmyhal confirmed on Friday that he, President Volodymyr Zelenskyy and the speaker of Parliament had signed a formal fast-track membership application for the NATO military alliance.

President Volodymyr Zelenskyy’s statement Friday came shortly after Russian President Vladimir Putin signed treaties to annex occupied areas of Ukraine that he warned he would protect using “all available means.”

Zelenskyy said, “we are taking our decisive step by signing Ukraine’s application for accelerated accession to NATO.”

The Ukrainian leader’s NATO application adds another layer of complexity to the seven-month-old conflict that rapidly escalated following Putin’s announcement of annexing parts of Ukraine.

Zelenskyy also repeated his pledge to retake all Ukrainian territory now held by Russia, which he said “feels our power.” He also said Ukraine is ready for dialogue with Moscow but “with another president of Russia.”

NATO was not immediately able to respond to The Associated Press’ questions about what Ukraine’s “accelerated” application to join the alliance would mean.

Ukraine is already considered an “aspirant country” for membership in the world’s biggest security alliance, along with Georgia. All 30 NATO allies would have to agree for the country to join.

NATO is wary of allowing any country to join when its borders and territory are not clearly defined. NATO’s Article 5 defense clause — the pledge that all allies must come to the aid of any ally who’s territory is under threat — would be compromised in the case of Ukraine, as it’s unclear what parts of the country would join.

Member countries have previously warned that it would take several years for the conflict-torn country to be able to join.

The Associated Press and Reuters contributed to this report.