Andriy Yermak's comments come as President Volodymyr Zelenskyy publicly considers the possibility of a negotiated settlement to the war with Russia, launched by Moscow's full-scale invasion of its neighbor in February 2022.
"Not just yet today," Yermak told Suspilne when asked whether Ukraine was ready to embark on talks.
"We don't have the weapons; we don't have the status that we are talking about. And that means an invitation to NATO and an understanding of clear guarantees that would provide for us so that we could be sure that (Russian President Vladimir) Putin won't be coming back in two to three years."
In comments this week alongside German opposition leader Friedrich Merz, Zelenskyy said Ukraine wanted an end to the war and efforts were needed to make his country stronger and oblige the Kremlin to work towards peace.
In recent public pronouncements, the president has also said talks could take place with Russia still holding on to territory it has seized in the invasion.
But Ukraine, he said, needed an invitation issued to the entire country to join NATO, though the Alliance's status would apply to the territory controlled by Kyiv authorities and real security guarantees had to be put in place.
While in Paris last week, Zelenskyy met U.S. President-elect Donald Trump, who has said, without giving details, that he wants the war to end quickly.
Russia has long rejected any notion of Ukraine becoming a NATO member, with Putin saying Kyiv had to accept the Kremlin's annexation of four Ukrainian regions it only partly controls.
