Further heightening tensions, an explosion deep inside Russia wounded three people on Sunday. Russian authorities blamed a Ukrainian drone for the blast, which damaged residential buildings in a town just 175 kilometres south of Moscow.

Russia has said the plan to station tactical nuclear weapons in Belarus comes in response to the West’s increasing military support for Ukraine. Putin said on Saturday it was triggered by a UK decision to provide Ukraine with armour-piercing rounds containing depleted uranium.

Putin likened his plan to the US stationing its weapons in Europe, while insisting that Russia would not violate its nuclear non-proliferation promises.

Ukraine’s Foreign Ministry condemned the move in a statementon Sunday and demanded an emergency meeting of the UN Security Council.

“Ukraine expects effective action to counter the Kremlin’s nuclear blackmail by the UK, China, the US and France,” the statement read, saying these countries “have a special responsibility” regarding nuclear aggression.

Ukraine has not commented on Sunday’s explosion inside Russia. It left a crater about 15 meters in diameter and five meters deep, according to media reports.

Russian state-run news agency Tass reported authorities identified the drone as a Ukrainian Tu-141. The Soviet-era drone was reintroduced in Ukraine in 2014, and has a range of about 1,000 kilometres.

The explosion in the town of Kireyevsk in the Tula region, about 300 kilometres from the border with Ukraine came after the drone crashed when an electronic jamming system disabled its navigation.

Similar drone attacks have been common during the war, although Ukraine hardly ever acknowledges responsibility.

On Saturday, Putin argued that Belarusian President Alexander Lukashenko has long asked to have nuclear weapons in his country again to counter NATO. Belarus shares borders with three NATO members – Latvia, Lithuania and Poland.

Both Lukashenko’s support of the war and Putin’s plans to station tactical nuclear weapons in Belarus has been denounced by the Belarusian opposition.

Tactical nuclear weapons are intended for use on the battlefield and have a short range and a low yield compared with much more powerful nuclear warheads fitted to long-range missiles. Russia plans to maintain control over the ones it sends to Belarus, and construction of storage facilities for them will be completed by July 1, Putin said.

The US said it would “monitor the implications” of Putin’s announcement. So far, Washington hasn’t seen “any indications Russia is preparing to use a nuclear weapon,” National Security Council spokesperson Adrienne Watson said.

-AAP with Reuters