Russia and Belarus on Friday launched a long-planned joint military exercise involving thousands of troops that has raised concern in the West.

The exercises, dubbed “Zapad 2025,” or “West 2025,” are held in Belarus and Russia and will last through Tuesday.

They are intended to showcase close defense ties between Moscow and Minsk, as well as Russia's military might.

The Russia-Belarus exercises also have drawn worries in Kyiv and its Western allies of Latvia, Lithuania and Poland, which border Belarus.

When President Vladimir Putin sent troops rolling into Ukraine on Feb. 24, 2022, many of them crossed from Belarus after joint drills days before the attack.

Belarusian defense officials initially said about 13,000 troops would participate in the exercise that was to take place near its western border.

In May, however, its Defense Ministry said the number would be cut nearly in half, and that the main manoeuvres would take place deeper inside the country.

In Moscow, the Defence Ministry said Friday that parts of the exercise will be held on the Russian territory, as well as as the Baltic and the Barents Seas.