Ukrainian troops appear to have broken through Russian defensive positions in the south, according to initial reports out of the region.
Kyiv’s forces reportedly launched a significant mechanised operation in Zaporizhzhia, pushing towards the village of Robotyne.
A confused picture has emerged overnight and there are diverging claims about what is happening on the ground.
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News of the possible breakthrough comes as Volodymyr Zelenskyy hinted at a significant win on the frontline last night.
“By the way, today our boys had very good results at the front,” he said in his nightly video address.
“Good for them! Details will follow.”
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Ukraine has been tight-lipped about its highly anticipated counteroffensive, reinforced by tanks donated by a host of Western countries, including the UK.
According to the Institute for the Study of War (ISW) thinktank, the battlefield conditions around Robotyne as well as the composition of Russian forces there offer “important colour” to speculation about the Ukrainian counteroffensive.
The ISW said that geolocated footage shows a tank and two Ukrainian Bradley infantry fighting vehicles and a T-72 tank either disabled or abandoned about 2.5km (1.5 miles) due east of the village.
It added: “This geolocated point is beyond the forward-most pre-prepared Russian defensive fortifications in this area, indicating that Ukrainian forces managed to penetrate and drive through tactically challenging defensive positions.
“This kind of penetration battle will be one of the most difficult things for Ukrainian forces to accomplish in pursuit of deeper penetration”.
Russian sources provided a wide range of diverging claims as to the scale of both the attack and resulting Ukrainian losses, indicating that the actual results and Ukrainian losses remain unclear.
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Anonymous officials at the US Pentagon, reported in the New York Times, suggested the attacks mark an inflection point in Ukraine’s counteroffensive.
The Western officials noted this is an opportune moment for Ukrainian efforts given recent Ukrainian operations to clear Russian defensive positions, Russian command changes and continued Ukrainian artillery strikes.
Ukraine does not routinely comment on the state of the counteroffensive or its objectives, but there has been speculation that it could seek to drive its forces south to the Sea of Azov.
While undoubtedly very challenging, this could have the effect of cutting Russian forces in two and – crucially – cutting off the land bridge to Crimea.