"We might - especially being threatened like that, blackmailed by that, and pushed to it", Prystaiko told the BBC Radio 5 Live, commenting on whether his country could change its position on membership in the alliance.
The envoy claimed that Russia already borders NATO members, saying it "did not change the security situation" for Moscow, Sputnik reported.
Asked about the membership issue again, Prystaiko noted that "we are flexible trying to get a way out".
"If we have to go through some serious concessions - that's something we might do, that's for sure," he stressed.
The Ukrainian presidential office has since addressed the statement, saying that NATO aspirations are included in the Ukrainian Constitution, but noted that the ambassador needs to be given an opportunity to elaborate on what exactly he meant regarding membership in the bloc.
Ukraine is not a NATO member, but has a promise dating from a 2008 summit in Bucharest, that the country will eventually be given the opportunity to join. In 2019, Kiev amended the Ukrainian Constitution, setting membership in NATO and the EU as the nation's goals.
The issue of Ukraine's membership in NATO remains a stumbling block between Russia and the alliance. Moscow previously put forth security guarantee proposals for NATO and the US, suggesting limits on troop and missile deployments and suggesting that the bloc stop expanding near Russia's borders.
Washington, however, ignored this part of the proposals, while NATO refused to abandon its "open-door" policies, saying that Ukraine and Georgia may become part of the alliance.