Russian President Vladimir Putin on Monday ordered the regular size of the Russian army to be increased by 180,000 troops to 1.5 million active servicemen, in a move that would make it the second largest in the world after China's.

In a decree published on the Kremlin's website, Putin ordered the overall size of the armed forces to be increased to 2.38 million people, of which he said 1.5 million should be active servicemen.

According to data from the International Institute for Strategic Studies (IISS), a leading military think-tank, such an increase would see Russia leapfrog the United States and India in terms of the number of active combat soldiers it has at its disposal and be second only to China in size. The IISS said Beijing has just over two million active duty service personnel.

It's the third time Putin has expanded the army's ranks since sending his military into Ukraine in February 2022. The move comes as Russian forces push forward in eastern Ukraine on parts of a vast 1,000-kilometre frontline and try to eject Ukrainian forces from Russia's Kursk region.

Battlefield losses in Ukraine

Although Russia has a population more than three times larger than Ukraine's and has been successfully recruiting volunteers on lucrative contracts to fight in Ukraine, it has — like Kyiv's forces — been sustaining heavy battlefield losses, and there is no sign of the war ending anytime soon.

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Both sides say the exact size of their losses is a military secret.

Andrei Kartapolov, chairman of Russia's lower house of parliament's defence committee, said the increase in active troop numbers was part of a plan to overhaul the armed forces and gradually increase their size to match what he described as the current international situation and the behaviour of "our former foreign partners."

"For example, we now need to form new structures and military units to ensure security in the northwest [of Russia] since Finland, with which we border, has joined the NATO bloc," Kartapolov told Parlamentskaya Gazeta, the Russian parliament's in-house newspaper.

"And in order to carry out this process, we need to increase the number of troops."

3rd increase since 2022

Putin since 2022 had previously ordered two official increases in the number of combat troops — by 137,000 and 170,000, respectively.

In addition, Russia mobilized over 300,000 soldiers in September and October 2022 in an exercise which prompted tens of thousands of draft-age men to flee the country.

The Kremlin has said that no new mobilization is planned for now, however, and that the idea is to continue to rely on volunteers signing up to fight in Ukraine.

Dara Massicot, an expert in the Russian military at the Carnegie Endowment for International Peace think-tank, questioned whether Moscow was ready to foot the bill for the increase in active servicemen.

"There are ways to staff a standing 1.5-million force but the Kremlin will not like them if they are truly grappling with what that requires," Massicot wrote on X, the platform formerly known as Twitter.

"Are they really able to boost the defence budget to sustain procurement AND this requirement?"

Massicot, who has released a report on Russia's drive to regenerate its army, said Moscow could take the unpopular and difficult decision of expanding the draft size or change the law to allow more women to work in the military to reach such a goal.

"Look for signs that this is a real initiative to recruit and expand, and not a kind of show to intimidate others. The current volunteer method is working but has strains. This [the expansion] means more expense and strain," she said.