A source familiar with the Russian diplomatic note said that Moscow is expected to protest the missions and it is not yet clear whether it means that Russia will change its behavior in any way. But this person acknowledged that the note could signal a more aggressive Russian stance against the US and NATO as the war continues. CNN has previously reported that the United States believes that Russian President Vladimir Putin’s risk tolerance has increased and that he may be willing to take more aggressive action against the United States in response to its support for Ukraine. Asked to comment, a senior US official said: “We will not confirm any private diplomatic correspondence. What we can confirm is that, together with the Allies and partners, we are providing Ukraine with multibillion-dollar security assistance, which Ukraine has provided. “Our partners are using it with great success to defend their country against the unprovoked aggression of Russia and the horrific acts of violence.” The first flight from the US of the new $ 800 million aid to Ukraine is expected to arrive in the region in the next 24 hours, according to a senior defense official. The official said the material would be picked up at the border by Ukrainians and transported to the country. The manifesto is not revealed. Ukrainian President Volodymyr Zelensky has been urging the West for months for heavier equipment to effectively fight the Russians, who invaded Ukraine on February 24. Russia returned to northern Ukraine and its forces were finally unable to occupy the capital, Kyiv. However, Ukrainian and Western officials have since expected Russia to launch a major offensive in eastern Ukraine, which is a different type of territory and requires different types of weapons. “This is the first time we have provided them [155mm] “It reflects the kind of fighting that Ukrainians expect to face here in this more limited geographical area,” Pentagon spokesman John Kirby told reporters Wednesday, referring to the Donbass area of ​​eastern Ukraine. . Despite Russian protests, the United States is showing no signs of slowing down its military support for Ukraine. Pentagon officials met with defense contractors this week to discuss how to increase the production of the systems and weapons that Ukraine will need to continue fighting. “This [meeting] “It really focused on the kind of systems and weapons that were involved in the Ukraine war,” Kirby said on Wednesday, adding that “the ability to accelerate some of these production and expansion lines based on our large stockpile.” This story has been updated with additional references. CNN’s Kaitlan Collins and Barbara Starr contributed to this report.