The adviser to US President Joe Biden said on Wednesday that “he is hearing more and more often that the Ukrainian army is rationalizing ammunition or even running out of ammunition at the front”, according to the France Presse agency.

“Every day the cost of US inaction increases for brave Ukrainians on the front lines,” said White House National Security Adviser Jake Sullivan.

He called on the US Congress to “quickly” transfer new financial aid to Ukraine.

“The Ukrainians will find themselves in a less stable position if they don’t get the ammunition, air defense systems and other equipment they need,” Sullivan said.

The new head of the Ukrainian army, Oleksandr Syrskyi, announced on Wednesday that together with Defense Minister Rustem Umerov, he visited the hottest areas of the eastern front and assessed the situation there as “extremely difficult and tense.”

“The Russian occupiers continue to increase their efforts and overwhelm” Ukrainian forces, Sirsky wrote on Telegram, while US military aid, which Ukraine needs to fight Russian forces, remains blocked for now.

The leader of the Republican majority in the House of Representatives (the lower house of the US Congress) refused on Tuesday to bring to a vote the bill on American aid to Ukraine, which was approved by the Senate on the same day. Democrats are in the majority.

The upper house of the US Congress voted in favor of a financial package of 95 billion dollars, about which there were fierce negotiations in recent months. The bill provides more than $60 billion for Ukraine, $14 billion for Israel, and funds for Taiwan.

In the absence of approval of a new financial package by the House of Representatives, the US aid to the Ukrainian army, interrupted since the end of December, will not be able to be restored.

For months, Democrats and Republicans have been at loggerheads in Congress over aid to Ukraine, an ally of the United States that has been at war with Russia for nearly two years.