Lithuania's parliamentary parties agreed on July 2 to remove the constitutional ban on nuclear weapons deployment and foreign military bases established over 30 years ago, reflecting shifting security concerns in the region [1, 2, 3]. Article 137 of Lithuania’s constitution explicitly forbids weapons of mass destruction and foreign military bases on Lithuanian soil [2, 3].

President Gitanas Nauseda said the provision was outdated, written under very different geopolitical conditions. "The geopolitical situation is getting worse. Our constitution was written when geopolitical circumstances were totally different," Nauseda said [1]. He added, "It would be truly regrettable if we were to become a weak link or a 'gray zone' within NATO itself," emphasizing the need for flexibility [3].

While Lithuania has no immediate plans to host nuclear weapons, officials said lifting the ban preserves the option should security conditions deteriorate further [1, 2, 3]. Defence Minister Robertas Kaunas noted Lithuania is practically the only NATO country with such a prohibition, which limits Lithuania’s ability to fully utilize alliance defense potential [3]. Prime Minister-designate Mindaugas Sinkevičius called the change politically appropriate, citing that neighboring countries’ constitutions lack such restrictions [3].

Lithuania has sharply increased its defense spending since Russia invaded Ukraine in 2022, nearly tripling expenditures [1]. The country will also host a permanently based German combat brigade from 2027 to bolster defense [1].

Lithuania remains a party to the nuclear Non-Proliferation Treaty despite the constitutional change [1]. The repeal follows Finland’s recent removal of a similar ban after joining NATO [1, 2, 3].

The constitutional amendment requires two-thirds majorities in two separate parliamentary votes and might be adopted by the end of 2026 [1]. The decision received near-unanimous support from party leaders, the president, prime minister-designate, and defense minister [1, 3].

In May 2026, President Nauseda vetoed legislation allowing nuclear-armed vessels into Lithuanian waters, reflecting cautious navigation of nuclear issues amid rising tensions [3]. The coming months will see further parliamentary actions toward formal repeal, with security and defense upgrades progressing in parallel [1].