Belarus says it is checking its army’s combat readiness. Analysts see little chance it will join Russia’s fight.

Belarus said on Tuesday that its army was assessing its combat readiness, a move that comes as the country has faced pressure to provide further support for Russia’s forces in Ukraine.

Military experts say it is highly unlikely that Belarus will send troops to Ukraine, not least because it would be deeply unpopular domestically, but they say that President Aleksandr G. Lukashenko of Belarus may be giving the impression of combat readiness in order to force Ukraine to divert troops from other fronts.

Mr. Lukashenko is a close ally of President Vladimir V. Putin of Russia, and Belarus relies on Moscow for finance, fuel and security assistance. Moscow used eastern Belarus as a staging ground when it launched its full-scale invasion of Ukraine in February. The United States and European governments have imposed sanctions on both countries.

A Belarusian Defense Ministry statement said that “a sudden check of combat readiness has begun” on the orders of Mr. Lukashenko.

As part of its preparations, Belarus’s troops will have to move to predetermined locations and test their equipment, organize security and defense and build bridges across the Neman and Berezina rivers, the Defense Ministry said on the Telegram messaging app.

The Neman river runs through Lithuania and eventually drains into the Baltic Sea, while the Berezina joins the Dnipro River around 40 miles north of the Ukrainian border. The exercises would not directly approach the frontier between Belarus and Ukraine, which is around 670 miles long.

In October, Mr. Lukashenko said that Russian troops would return to his country in large numbers, and in recent weeks drones have been launched from Belarus against Ukraine’s energy infrastructure and other targets. In addition, supplies of military equipment have been ferried by Russian forces from Belarus to their troops in eastern Ukraine’s Donbas region.

Ukrainian forces are already fighting in the south and east. In light of the potential threat from the north, Andriy Demchenko, a spokesman of Ukraine’s State Border Guard Service, said on Tuesday that the country was strengthening its defenses along the length of its border with Belarus. He said the situation is under control.

“We can clearly see how Russia is putting pressure on Belarus to join the full-scale war,” he said on a Ukrainian telethon.

Ukraine in recent weeks began to build a wall and trench system along the frontier in the northwestern province of Volyn, though analysts say that it is more likely to stop migrants crossing rather than for a military purpose.

The Institute for the Study of War, a research group based in Washington, said in a report this week that Belarus is “extraordinarily unlikely to invade Ukraine in the foreseeable future.”

Instead, it said that Mr. Lukashenko and other officials in Belarus have assisted with an effort by Moscow to suggest that Belarus will join the war directly in an effort to pin down Ukrainian troops on their northern border.

At the same time, the Institute said that Moscow aimed to bind Belarus further into its campaign in Ukraine “as part of a long-term effort to cement further control over Belarus.”