The five-month delay before the US Congress approved $61 billion in military aid to Ukraine may have inflicted enduring damage that will reverberate on the frontlines for months to come.

Russian forces capitalized on the “artillery drought” that has hindered Ukraine’s defenses since December, making significant advances on the eastern front near Avdiivka. This marks their most substantial progress since the early stages of the conflict. Moscow’s advancements have prompted warnings from senior Ukrainian military officials about the potential threat to Kyiv’s supply lines and eastern hubs, which are now dangerously close to falling within range of superior Russian firepower.

This concerning development precedes an anticipated Russian offensive in late May, which could jeopardize Ukraine’s presence in the Donetsk region and the hard-won, albeit modest, gains toward the occupied port city of Mariupol. Russia has allocated substantial resources to exploit weak Ukrainian defenses along the eastern frontlines, aiming for three key objectives: the crucial military hub of Pokrovsk, situated west of Avdiivka; the strategic heights of Chasiv Yar, near Bakhmut; and Kurakhove in the southeast.

Despite Ukraine’s announcement on February 17 of its withdrawal from Avdiivka—a town fiercely contested for a decade, one in which Russia appears to have sacrificed hundreds of troops to seize—Moscow’s onslaught did not cease. Over the ensuing 10 weeks, as illustrated by a CNN map and analysis from the Ukrainian monitoring group DeepStateMap, Russian forces gradually captured village after village to the west of Avdiivka. They exploited Kyiv’s failure to fortify defenses and reluctance to publicly acknowledge the extent of territorial losses in that area.

It wasn’t until Sunday that the top Ukrainian military commander, Oleksandr Syrskyi, acknowledged the capture of a series of villages that his subordinates had insisted were still contested for days. This retreat demonstrated that Russian forces had achieved their most substantial and rapid progress since the advances near Severodonetsk in July 2022, as per a CNN analysis.

The Ukrainian leadership’s reluctance to acknowledge these losses drew public criticism from some pro-Ukrainian military bloggers and analysts. DeepStateMap, which provides daily updates on the frontline situation, indicated significant losses near Avdiivka. One of the group’s founders, Ruslan Mykula, expressed their concern to CNN, stating that they felt compelled to speak out because a military spokesperson has the means to verify the real situation but continues to provide inaccurate information, thereby undermining credibility.

Mykula remarked that the recent Russian advances near Ocheretyne, a village captured by Russia in the past weeks west of Avdiivka, represent “a tactical success so far,” but could potentially evolve into “a strategic one.” He emphasized, “In the current scenario, halting the enemy’s advance will be exceedingly challenging because they are targeting areas where the defense was not adequately fortified.”

He pointed out a deficiency in defensive structures along the entire left flank of Avdiivka, leaving vast open plains vulnerable, extending nearly to a crucial highway leading to the strategic Ukrainian hub of Pokrovsk.

The latest update from the Ukrainian general staff on Tuesday indicated that their forces were defending a series of villages uncomfortably close to Pokrovsk. In his presidential address on Tuesday, Volodymyr Zelensky urged for a “significant acceleration of [Western] supplies to substantially bolster the capabilities of our soldiers.” He stressed the necessity for fortified defenses, particularly in the direction of Pokrovsk, alongside other vulnerable frontlines to the south near Kurakhove, as well as to the northeast near Kupiansk.

Further Russian advances toward Kurakhove in the southeastern sector of the frontline could jeopardize the gains made by Ukraine during the summer counteroffensive. Meanwhile, to the north, Russia is intensifying bombardments on Kharkiv, Ukraine’s second-largest city, while simultaneously exerting pressure along the frontlines near Kupiansk to regain territory liberated by Ukraine during a swift advance in the late summer of 2022.

Ukrainian officials have raised alarms about the looming threat to Chasiv Yar, a small town near the city of Bakhmut, which was forcibly seized from Ukrainian control last May. Perched atop a hill, Chasiv Yar holds strategic significance. Lt. Col Nazar Voloshyn, spokesman for the Ukrainian Khortytsia command, stated on Ukrainian television on Tuesday that Russian forces are targeting the canal near the town, intending to capture it to secure a strategic advantage over vital nearby Ukrainian military towns.

Voloshyn emphasized the urgency of the situation, stating, “It would be crucial for them to seize Chasiv Yar before we receive foreign aid and before our ammunition shortages are resolved.” He warned of the ramifications if the enemy were to capture the high ground, stating, “If the occupiers establish a foothold there, it will pose a significant threat, as towns like Kostiantynivka, Kramatorsk, Sloviansk, and Druzhkivka would immediately come under attack.”

If these four towns, all situated along the same highway, were to face a significant threat of capture, Russia’s objective of gaining control over the entire Donetsk region would be significantly closer to realization.

Yurii Fedorenko, commander of the Achilles attack drones company at the 92nd separate assault brigade in the area, noted that the next two months represent a “window of opportunity” for Russian forces. He highlighted that Russian forces have recognized that Ukraine will soon possess the required air defense capabilities and a sufficient stockpile of ammunition concentrated on the frontline. This would render it impossible for the enemy to maintain its current intensity of operations.