Kyiv has sounded the alarm that Russia may use Belarus – a springboard for its 2022 invasion of Ukraine – to stage a new offensive from the north, including towards the capital.

Ukraine’s Security Service (SBU) said its units and the army were “carrying out a comprehensive set of enhanced security measures in the northern regions of our country”.

The measures – including stepped up checks and controls of individuals and properties – “will serve as an effective deterrent to any aggressive actions or operations by the enemy and its ally”, the SBU said in a statement.

The Kremlin on Monday dismissed Ukraine’s allegations it wanted to drag Belarus further into the war as “an attempt at further incitement”.

Russia and Belarus are staging joint nuclear drills this week, involving thousands of troops, planes and strategic missile forces.

Amid the exercises, Zelensky said on Wednesday that his country was “preparing responses to every possible course of enemy action – if the Russians do indeed dare to expand their aggression”.

Hundreds of thousands of people have been killed since Russia invaded Ukraine in 2022, with the war having spiralled into Europe’s deadliest conflict since World War II.