Russian lawmakers Tuesday backed legislation increasing the maximum age limit to 30 for compulsory military service, over a year into the Russia-Ukraine war.

The bill comes as Moscow seeks to replenish its forces on the front line in Ukraine without resorting to another mobilization.

"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.

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.