Ukraine’s parliament approved measures Thursday that reinstated partial civilian conscription and rotated war-weary troops away from the front lines of the nation’s conflict with pro-Russian separatist forces. The vote was taken in support of President Petro Poroshenko’s plan to maintain combat readiness amid evidence of increased Russian military activity in eastern Ukraine.

“There is an urgent need to strengthen the combat- and mobilization-readiness of our forces and other military forces up to a level that guarantees an adequate reaction to threats to national security from continuing Russian aggression,” said Oleksander Turchynov, secretary of Ukraine’s national defense council, according to Reuters. Poroshenko had previously implored parliament to rotate veteran reservists to the front lines. The implementation of partial conscription – last used in 2013 after the removal of pro-Russian former President Viktor Yanukovich – will allow Ukraine’s military to enlist civilians to bolster its forces.

Approximately 8,500 Russian troops are currently active in eastern Ukraine, Turchynov told Congress. Russian leaders have repeatedly denied they directly intervened in the battle between Ukrainian government forces and pro-Russian separatists, despite continued accusations from Kiev and the United States. Nearly 5,000 have been killed in the conflict.

The renewed military measures come days after Russian and Ukrainian leaders canceled a scheduled peace summit, citing a lack of progress in negotiations. A September ceasefire in the Ukranian conflict has failed to end hostilities between the two sides. Brokered by French and German officials, the summit would have occurred Thursday in Astana, Kazakhstan.

An offensive by pro-Russian rebels in the heavily contested Donetsk region caused the collapse of an air traffic control tower at Donetsk Airport, reports said. The separatists reportedly warned Ukrainian government forces to surrender or face annihilation. Bolstered by tanks and artillery, rebel forces seized control of a portion of the airport Wednesday as the fight for control of the key landmark continued.