Russian forces tried to break through Ukrainian defenses all along the Donetsk, Luhansk and Kharkiv fronts on Monday, the Ukraine Security Council Secretary said, according to Reuters. Russia appears to have attempted to start the active phase of its new eastern offensive this morning, the Security Council official added. 

The official stated that they think Ukrainian forces in Donetsk and Luhansk can withstand the new Russian assault, but warned that the threat to cities from long-range rocket attacks has become much higher. 

Additional Updates on Monday

These comments come after Ukrainian's Armed Forces Command said on Monday that they see signs that Russia is beginning its new offensive in eastern Ukraine. Russia's main military target is focused on taking full control of the Donetsk and Luhansk regions, Armed Forces Command added. 

Ukraine's Defense Ministry also stated on Monday that Russian aircraft bombing runs in Ukraine have increased by 50%. 

The recent escalation of the fighting in Ukraine comes after Ukrainian President Volodymyr Zelenskyy said over the weekend that talks with Russia are at a "dead-end", given that Ukraine will not trade away its territory or people. 

Moreover, if Russian forces follow through on threats to destroy the remaining Ukrainian troops in Mariupol, this would "put an end" to peace talks, Zelenskyy warned.