For Ruslan, an engineer in the Belarus capital of Minsk, Russia’s war in neighboring Ukraine suddenly seemed closer than ever when a conscription office recently sent him a summons for military training.

It’s part of an effort that will see thousands of men in Belarus attend drills amid fears that the staunch Moscow ally could be drawn into the fighting.

“They are telling us that Belarus won’t enter the war against Ukraine, but I hear Russian warplanes roar over my house heading to the Machulishchi air base outside Minsk,” the 27-year-old told The Associated Press in a telephone interview. He asked not to be fully identified out of concern for his personal safety.

“Russian troops are already in Belarus, and I see the country gradually being turned into a military barracks,” he said. “Everybody fears that they won't allow Belarusians to keep watching the war from a distance for too long.”

Belarus President Alexander Lukashenko has welcomed thousands of Russian troops to his country, allowed the Kremlin to use it to launch the invasion of Ukraine on February 24, 2022, and offered to station some of Russia’s tactical nuclear weapons there. But he has avoided having Belarus take part directly in the fighting — for now.

Analysts and political opponents say that further involvement over Ukraine could rekindle public anger against him and erode his iron-fisted grip on power that has lasted for nearly 29 years.

Lukashenko, who meets regularly with Russian President Vladimir Putin, has relied on the Kremlin’s political and economic support to survive months of protests, mass arrests and Western sanctions following an election in 2020 that kept him in power and was widely seen at home and abroad as rigged.

Russia’s invasion is deeply unpopular in Belarus, which shares a 1,000-kilometer (620-mile) border with Ukraine and has many citizens with family or personal ties there.

“The Belarusians don’t see any sense in this war,” said Svyatlana, a 54-year-old manager in Luninets, near the border. She asked not to be identified by her full name for her own security.

A new Belarusian air defense unit was formed recently in the city, she said, and “war fears have increased” as troop numbers have grown.

Belarusian military analyst Aliaksandr Alesin said that if the country’s 45,000-member army is sent into Ukraine, there might be “mass refusals to follow orders.”

He said Lukashenko won’t do it “because he fears to stir up discontent among the military, who could turn their weapons in a different direction.”

While agreeing to station some of Russia’s tactical nuclear weapons in his country, Lukashenko cast the move as protection against what he described as NATO’s aggressive plans and Western plots against his government.

“They don’t bomb countries with nuclear weapons,” Lukashenko said recently.

The construction of storage facilities for tactical nuclear weapons in Belarus will be finished by July 1, Putin said. Russia already has modified Belarusian warplanes to carry nuclear weapons and given its ally Iskander short-range missiles that can be fitted with a nuclear warhead. It also has trained Belarusian crews to operate the planes and missiles armed with nuclear weapons.

During the Cold War, Belarus hosted about two-thirds of Moscow's arsenal of nuclear-tipped intermediate range missiles, Alesin said, adding that dozens of Soviet-era storage sites can still be used for such weapons. Soviet nuclear weapons stationed in Belarus, Ukraine and Kazakhstan were moved to Russia under a US-brokered deal after the USSR's collapse in 1991.

“Belarus was a Soviet nuclear fortress, and now Putin and Lukashenko have decided to not only restore but to strengthen it,” Alesin told AP. “From Belarus, Russian nuclear-tipped missiles could reach Ukraine, the entire territory of Poland, the Baltics and part of Germany, and this ‘Belarusian nuclear balcony’ will rattle Western politicians’ nerves for a long time to come.”

Opposition leader Sviatlana Tsikhanouskaya, who challenged Lukashenko in the 2020 election after her activist husband was jailed, told AP that hosting Russian nuclear weapons would turn the Belarusian people into hostages.

“The deployment of Russian nuclear weapons will make Belarus a target in case of an escalation and seriously jeopardize Belarusians’ lives,” said Tsikhanouskaya, who fled the country after the election and has become a fierce critic-in-exile of Lukashenko. “The two dictators have gone too far in their war games, and it will only lead to the toughening of Western sanctions.”

Those sanctions have crippled the Belarus economy, which shrank by a record 4.7 percent last year. Lukashenko hopes a 70 percent surge in trade with Russia last year will soften the impact and expects Belarus will profit from Moscow’s orders for electronics and other high-tech components for weapons systems.

Alesin said Moscow is providing Minsk “with cheap energy and loans and opens up its vast market in exchange for the opportunity to control the Belarusian military infrastructure.”

Some of the 300,000 Russian reservists called up last fall by Putin as part of his partial mobilization are being trained on firing ranges in Belarus. Lukashenko has said 500 officers are helping train the Russians, who are camped next to Belarusian barracks.

But this growing involvement in Belarus for the Kremlin war efforts is fomenting widespread resentment, said Belarusian political analyst Valery Karbalevich.

“A broad guerrilla movement has evolved in Belarus with its members blowing up railway tracks and Russian warplanes and attacking Russian and Belarusian official websites,” Karbalevich said. “Belarus’ transformation into a Russian military hub and its gradual drawing into the war has caused public discontent, forcing Lukashenko to escalate repressions.”

BYPOL, an organization of former military and security officers who oppose Lukashenko, claimed responsibility for a February drone attack on a Russian A-50 early warning and control aircraft at the Machulishchi air base near Minsk. Authorities said they detained a suspect alleged to be behind the attack, along with 30 others who were charged with terrorism and could face capital punishment if convicted.

Raids across the country have resulted in 300 other arrests on suspicion of links to the guerrillas, according to the Viasna human rights center.

BYPOL leader Aliaksandr Azarau told AP that if Belarus enters the war in Ukraine, it would provide a boost for his group, which grew out of the 2020 election protests.

“If small Belarus starts getting coffins from Ukraine, it will inevitably stir up protests that the authorities barely managed to stifle with mass repressions,” he said. “Lukashenko reasonably worries that entering the war would lead to a sharp rise of the guerrilla movement.”

When Putin launched the invasion, Russian troops rolled into Ukraine from Belarus in an ultimately unsuccessful attempt to capture Kyiv, only 90 kilometers (about 55 miles) to the south. Parts of western Ukraine, including railway hubs of Lviv and Lutsk that are key conduits for Western weapons, also could be vulnerable to a potential incursion from Belarus.

Ukrainian President Volodymyr Zelenskyy recently visited border guards in the northwestern Volyn region, urging vigilance against a possible incursion from Belarus.

“We haven’t seen any preparations in Minsk, and Lukashenko so far has resisted being drawn into a war with Ukraine, but the situation may change as Belarus is getting increasingly militarized,” said Ukrainian military analyst Oleh Zhdanov. “Lukashenko is ready to give Putin whatever he wants — except the Belarusian soldiers. But we aren’t blind and Kyiv is seriously worried about a sharp increase in the Russian military presence in Belarus.”

Karbalevich, the Belarusian analyst, said that while Lukashenko probably will remain reluctant to enter the war, Moscow could dangle the threat of another incursion into Ukraine from Belarus to force Kyiv to keep a significant number of troops on the border.

“The poorly motivated and weak Belarusian military army wouldn’t make much of a change on the battlefield, but the Kremlin needs to keep showing Kyiv and the West that the Belarusian threat remains,” he said. “It’s more convenient for Putin to use Minsk as a military hub while maintaining the constant threat of Belarus entering the war to keep the pressure on Ukraine.”