Delays in weapons deliveries from Western allies to Ukraine are opening a door for Russian battlefield advances, Ukrainian President Volodymyr Zelensky says, making the fight “very difficult” along parts of the front line where the Kremlin’s forces captured a strategic city last weekend ahead of the war’s two-year anniversary. Ednews informs the following referring to AP.

Zelensky and other officials have often expressed frustration at the slowness of promised aid deliveries, especially since signs of war fatigue have emerged. European countries are struggling to find enough stocks to send to Kyiv, and U.S. help worth $60 billion is stalled over political differences. That appears to be playing into the hands of Russian President Vladimir Putin.

Even so, more help is heading Ukraine’s way, as Sweden announced Tuesday its biggest aid package so far and Canada said it was expediting the delivery of more than 800 drones.

Zelensky, in his daily video address late Monday, said Russia has built up troops at some points along the 1,500-kilometer (930-mile) front line, apparently aiming to pounce on any perceived defensive weaknesses.

“They (the Russians) are taking advantage of delays in aid to Ukraine,” he said after visiting the command post in the area of Kupiansk, in the northeastern Kharkiv region, on Monday.

He said Ukrainian troops keenly felt a shortage of artillery, air defense systems and long-range weapons.