Ukraine says Russia is holding back units as Ukrainian counterattack near Kharkiv unfolds:

The Ukrainian military says that Russia is holding back some of its forces within its borders to prevent a Ukrainian counterattack that has made some headway east of Kharkiv.
In its latest operational update, the armed forces' general staff says that "in order to prevent the advance of units of the Armed Forces of Ukraine, the enemy has concentrated up to nineteen battalion tactical groups in the Belgorod region" of Russia.
The Russians are holding back units as Ukrainian units get closer to the Russian border, analysts say.
Inside Ukraine, the general staff says the most intense activity is in Donetsk region, where Russian forces are trying to advance towards the town of Lyman, a major transport hub.