Belarusian leader Alexander Lukashenko announced on Thursday that Russia has stationed its newest nuclear-capable Oreshnik missile system in Belarus, a development unfolding as negotiations aimed at ending the war in Ukraine reach a decisive stage. According to Lukashenko, the intermediate-range ballistic missiles arrived on Wednesday and are now being placed on active combat alert. He did not disclose how many missiles were deployed or provide further specifics.

Russian President Vladimir Putin had stated a day earlier that the Oreshnik system would be operational by the end of the month, though he also withheld details. Speaking during a meeting with senior military officials, Putin cautioned that Russia would attempt to consolidate and expand its territorial advances in Ukraine if Kyiv and its Western supporters reject Moscow’s terms during peace talks.

U.S. President Donald Trump has launched a broad diplomatic effort to bring an end to nearly four years of conflict following Russia’s full-scale invasion of Ukraine in February 2022. However, those efforts have stalled due to starkly opposing demands from Russia and Ukraine.

Russia has already positioned tactical nuclear weapons in Belarus, a close ally whose territory was used as a staging ground for the 2022 invasion. Lukashenko has previously acknowledged that Belarus hosts several dozen Russian tactical nuclear warheads.

The Oreshnik missile—named after the hazelnut tree—was first tested in November 2024 in a conventional strike on a Ukrainian industrial facility. Putin has claimed the missile is impossible to intercept and warned that Russia could potentially use it against countries backing Ukraine that permit strikes on Russian territory using long-range weapons.

Putin has also asserted that the missile’s multiple warheads descend at speeds approaching Mach 10 and cannot be stopped by existing defenses. He has suggested that even a conventional strike using several Oreshnik missiles could rival the destructive impact of a nuclear attack. Russian state media has claimed the missile could reach a Polish air base in 11 minutes and NATO headquarters in Brussels in 17 minutes, noting that it would be impossible to determine whether the missile carried a nuclear or conventional payload before impact.

Intermediate-range missiles, capable of traveling between 500 and 5,500 kilometers (310 to 3,400 miles), were previously banned under a Cold War-era arms control treaty abandoned by both Washington and Moscow in 2019. Putin and Lukashenko had earlier said the Oreshnik would be deployed in Belarus before the end of the year.

When the two leaders signed a security agreement in December 2024, Putin stated that although Russia would retain control over the missiles, Belarus would be allowed to choose their targets. He added that missiles aimed at closer targets could carry heavier payloads.

Last year, Russia revised its nuclear doctrine to state that any conventional attack on Russia supported by a nuclear-armed nation would be treated as a joint assault. The change appeared designed to deter Western support for Ukrainian long-range strikes and significantly lowered the threshold for potential nuclear use. The updated doctrine also formally extended Russia’s nuclear protection to Belarus.

Lukashenko has governed Belarus, a country of 9.5 million people, for more than 30 years, maintaining tight control over political life. His government has faced repeated Western sanctions over human rights abuses and for allowing Russian forces to operate from Belarusian territory during the invasion of Ukraine.

Despite his close alignment with Moscow, Lukashenko has recently attempted to improve relations with Washington. On Saturday, he released 123 political detainees—including Nobel Peace Prize winner Ales Bialiatski—following an agreement with the United States that resulted in the lifting of U.S. sanctions on Belarus’s potash industry, a major source of export revenue.

Belarusian opposition figure Sviatlana Tsikhanouskaya told The Associated Press that the deployment of the Oreshnik system further entrenches Belarus’s political and military reliance on Russia.

“Bringing Oreshnik missiles into Belarus turns the country into a military target and deepens its militarization, and we strongly oppose it,” Tsikhanouskaya said. “Putin is using Lukashenko as a pawn in the Kremlin’s strategic maneuvers.”