Ukraine has prepared an array of new military units for its long-anticipated counteroffensive this summer, while its established brigades weathered Russia's winter offensive in the east.
The first phase of the counteroffensive has begun. Here's what we know about the new Ukrainian units.
TWELVE BRIGADES
NATO allies and partners helped Ukraine equip and train nine new armoured brigades for the counteroffensive, the military alliance's Secretary General Jens Stoltenberg confirmed in April.
A U.S. intelligence document made public in the Discord leaks said Ukraine had also prepared three more brigades itself.
The document identified the nine brigades as the 47th, 33rd, 21st, 32nd, 37th, 118th, 117th and 82nd brigades. The name of the ninth one could not be made out.
A brigade typically has at least 3,500-4,000 troops, but exact numbers are not known.
By April, Ukrainian units had received more than 1,550 armoured vehicles, 230 tanks, other equipment and vast amounts of ammunition, Stoltenberg said. More supplies have followed since.
In mid-May, one Russian military blog noted a buildup of Ukrainian forces and equipment in southeastern Zaporizhzhia region and the neighbouring Dnipropetrovsk region, estimating Kyiv's troop numbers at 50,000-55,000.
ASSAULT UNITS
Ukraine has separately created eight new assault brigades totalling 40,000 soldiers, according to Interior Minister Ihor Klymenko. The units drew from an aggressive recruitment campaign that began at the start of February.
The units have catchy or well-known Ukrainian names, including Azov, Kara Dag (a mountain in Crimea), Border of Steel, Hurricane, Spartan, Chervona Kalyna, Frontier and Rage.
Members of one of the units told Reuters in April that they wanted to be involved in frontline fighting and were highly motivated and wanted to "take revenge" on Russia.
ARE ANY OF THESE UNITS FIGHTING YET?
The 47th, 33rd and 21st mechanised brigades have been spotted in combat in the southeast in the last two weeks, as the main phase of the counteroffensive has got under way, some Western military analysts say.
The bulk of Ukraine's forces are yet to be committed.
Analysts poring over battlefield images released by Russia believe the 47th lost some equipment in the fighting, including Bradley infantry vehicles, though they say that the images may not tell the whole story.
Valerii Markus, a prominent Ukrainian field commander and one of the brigade's leaders, said on social media last week that his forces had suffered only small losses and that they had inflicted heavy casualties on the Russian side.
The new brigades are thought to contain mostly newly mobilised soldiers led by experienced officers.
During the fighting of the last few weeks military analysts have also spotted the presence of more experienced units such as the 68th Jaeger brigade and 35th Marine Brigade in the south.
That could suggest Ukraine is attaching battalions or companies of more established units to the newer forces it has prepared to increase overall battlefield experience, military analysts say.
