3rd Army Corps (Ukraine)

The 3rd Army Corps (Ukrainian: Третій (3-й) армійський корпус, abbreviated as 3 АК^[4]) is a Corps of the Ukrainian Ground Forces formed in 2025.^[5][6] The corps is led by colonel Andriy Biletsky, the founder and first commander of both the Azov Battalion and the 3rd Assault Brigade.^[7][8]

In February 2025, amid a large restructuring within the Ukrainian military which introduced the corps structure above the brigade level, it was reported that the 3rd Assault Brigade would form the nucleus of a new corps.^{[9][10][11][12]}

On 14 March 2025, colonel Andriy Biletsky, commander of the 3rd Assault Brigade, officially announced the formation of the 3rd Army Corps under his command.^{[9][12][13][14]} The corps began operating the same month.^[4][15]

On 23 March, it was reported that units of the corps, primarily the 3rd Brigade's 1st Assault Battalion, had restored Ukrainian control over the village of Nadiia, located on the border of the Luhansk and Kharkiv regions.^[16][17]

In May, Ukrainian military journalist Yurii Butusov wrote that once all the bureaucratic processes relating to the formation of the corps were completed, it would be able to deploy its forces to stabilize the Kupiansk and Lyman fronts.^[18][19]

According to Butusov, on 4 June, amid an "extremely critical situation" on the front, the transition to the corps command system was implemented, and the entire 120-kilometre (75 mi) line held by the constitutent units of the 3rd Army Corps was formally placed under Biletsky's command.^[20] This included the areas of responsibility of two Ukrainian brigades where the Russians had managed to advance significantly during the first half of 2025.^[21][22]

In late July, Butusov credited Biletsky with establishing order and improving the situation on the front and repelling the offensives of Russia's 20th and 25th Combined Arms Armies, supported by units of the 1st Guards Tank Army.^[21][23] In an early August interview, lieutenant colonel Maksym Zhorin said that the 3rd Army Corps had managed to stop the offensive operations of Russia's 20th Combined Arms Army and 22nd Army Corps, claiming that on certain sections the front, the Russians had been pushed back 4–5 kilometres (2.5–3.1 mi) and 8 kilometres (5.0 mi).^[1][24] The same month, it was reported that the corps held a 120-kilometre (75 mi) front line between the cities of Lyman (Donetsk region) and Borova (Kharkiv region).^[25][26]

In May 2025, Biletsky announced that the 3rd Army Corps would consist of five brigades, including mechanized brigades, assault brigades, and one heavy mechanized brigade.^[9][27][28]

In mid-July, the 3rd Army Corps received Patria six-wheeled armored personnel carriers from Latvia, at a ceremony involving Latvian prime minister Evika Siliņa and corps commander Biletsky, who said that the APCs were the best and possibly the most modern that his unit had ever operated.^[35][36][37]