Ukrainian President Volodymyr Zelenskyy spoke out against American critics who are pushing for cuts to military support to his country stating there are "dangerous voices" in Congress and in the U.S.

Zelenskyy told reporters Wednesday that his team was in constant contact with National Security Advisor Jake Sullivan and other U.S. national security officials, stating he was "glad" Ukraine had the backing of the White House, enjoyed bipartisan support in Congress and received “a lot” of support from the American public.

However, Zelenskyy said the coming year will be "very difficult," referring to the U.S. presidential election, which "will definitely have an impact on support for Ukraine."

"I think we’re going to have a hard time," Zelenskyy said.

He said the election results could be positive or negative for Ukraine.

“For our part, we will do everything to ensure that the support of the United States does not decrease…we will give all our time, our energy to constantly work with the USA," Zelenskyy said. “I expect that our partners in the United States will continue to be our partners and friends.”

Zelenskyy said Ukraine was working on lobbying Biden for longer range missiles.

-ABC News' Tom Buridge and Natalya Kushnir

The U.S. Department of Defense announced an additional $400 million aid package to Ukrainian forces that includes more weapons and ammunition.

This marks the Biden administration's 43rd military aid package to Ukraine since August 2021.

Some of the equipment and weapons in this package include, additional munitions for Patriot air defense systems and National Advanced Surface-to-Air Missile Systems (NASAMS); Stinger anti-aircraft systems and Javelin and other anti-armor systems and rockets.

-ABC News' Matthew Seyler

Ukraine has begun using the controversial cluster munitions that the U.S. recently began providing to Ukraine, a U.S. official confirmed to ABC News.

Ukraine, Russia and the U.S. are not signatories to the convention that bans the use of cluster munitions. Russia has used them in the war in Ukraine and so has Ukraine as they a supply of the weapons left over from the Soviet era.

"I believe they have started using them," Pentagon deputy press secretary Sabrina Singh said Thursday. "In terms of the effect on the battlefield, I'd really let Ukraine speak to how they intend to employ them. But you know, this is a powerful artillery that we have given them. They have ... committed to use it responsibly, to keep track and record where they are using it, so when this war is over, they can begin those de-mining efforts."

The weapons are considered dangerous to civilians because the small bomblets that are dispersed by the munitions can remain unexploded until someone accidentally stumbles upon them weeks, months or even years later.

-ABC News' Luis Martinez

Russian forces hit a three-story building and a garage in the city center of Mykolaiv Thursday morning, local time, injuring nine people, including five children, the Mykolaiv Regional State Administration said on Telegram.

There were fatalities stemming from the strikes, but it's unclear how many at this time, the Mykolaiv Regional State Administration added.

In another incident, Russian strikes hit Odesa early Thursday morning, the Odesa District Administration said on Telegram.

Two people were injured and hospitalized from the attack, according to the Odesa District Administration.

There is destruction "in the center" of Odesa and a fire broke out stemming from the strikes, the administration said.

-ABC News' Natalia Kushniir and Yuriy Zaliznyak

Ukrainian Armed Forces have yet to reach their "full potential," but two top generals exclusively told ABC News the counteroffensive is "going to plan" despite concerns from Western analysts that Ukraine is not making enough progress.

Gen. Oleksandr Tarnavskyi, who is leading the counteroffensive in the south, told ABC News' chief global affairs correspondent Martha Raddatz that the situation is "stable."

"The main thing is that we haven’t reached our full potential," Tarnavskiy said.

Ukrainian troops launched the counteroffensive a month ago, attacking on multiple axes on the southern frontline in Zaporizhzia using Western-supplied vehicles. Ukraine succeeded in piercing Russian lines at two points, liberating a string of villages, but has since been locked in ferocious fighting

Gen. Oleksandr Syrskyi, commander of the Ukrainian ground forces, told Raddatz that last month's failed rebellion by the Putin-backed PMC, the Wagner Group, wouldn't impact the fighting on the ground.

"It would be better for us if there were some negative consequences in Russia itself, but it doesn't matter for me," he said.

Asked if he was confident of retaking the key city of Bakhmut, Syrskyi said, "Yes, of course. I’m sure."

Both sides have suffered heavy casualties, according to Western officials, particularly in the south where Russia has so far conducted "relatively effective defensive operations" in the southeastern Zaporizhzhia province, the U.K. Ministry of Defense reported.

"The enemy is suffering eight times or even 10 times higher losses, especially with the number of killed troops," Syrksyi said.

-ABC News' Guy Davies and Meghan Mistry