Ukrainian troops, outnumbered by Russian ground forces, are retreating from positions in eastern Ukraine as Russian troops advance westward, Ukrainian Colonel General Oleksandr Syrskyi said Sunday.

Ukrainian President Volodymyr Zelenskyy also made fresh pleas to allies to send more Patriot air defense systems “as soon as possible,” VOA reported. 

Syrskyi said that Kyiv's outnumbered troops had fallen back to new positions west of three villages on the eastern front where Russia has concentrated significant forces in several locations.

"The situation at the front has worsened," the top general wrote on the Telegram messaging app, saying the "most difficult" areas were west of occupied Maryinka and northwest of Avdiivka, a strategically important town captured by Russian forces in February.

Ukrainian forces face a worsening position in the east while awaiting delivery of US weapons following the approval by Congress of a $61 billion aid package for Ukraine.