Russian lawmakers on Tuesday backed legislation increasing the maximum age limit for compulsory military service to 30, over a year into the Kremlin's Ukraine offensive.
The bill comes as Moscow seeks to replenish its forces on the front line in Ukraine without resorting to another mobilisation -- a step the Kremlin took last September which proved unpopular.
"From January 1, 2024, citizens aged 18 to 30 will be called up for military service," the lower house of parliament said after the bill was passed in a second and third reading.
The law also prohibits conscripts from leaving the country once the enlistment office has sent them their draft notice.
It still has to be approved by the upper chamber and signed into law by President Vladimir Putin, steps that are considered a formality.
Previously, one year of military service was mandatory in Russia for men aged 18 to 27 with conscription carried out twice a year.
Lawmakers also said they were dropping an initial proposal to gradually shift the conscription age to between 21 and 30.
"The wording of the draft law changed because the demographic situation is serious and affects the volume of the mobilisation resource," Andrei Kartapolov, head of the Duma's defence affairs committee, told the Interfax news agency.
Also on Tuesday, the Duma passed a bill significantly increasing fines for those who fail to show up at an enlistment office after a draft notice is received.
They will be risking a fine of up to 30,000 rubles (around $330) when the law comes into force on October 1. The maximum fine is currently 3,000 rubles.
Tens of thousands of men fled Russia last autumn after Vladimir Putin announced a mobilisation of 300,000 reservists to prop up Moscow's forces in Ukraine.
In April, Russian lawmakers adopted a law creating a digital conscription notice system. It allowed call-up papers to be served online instead of in person, greatly facilitating the mobilisation of Russians into the army.