Pentagon announced on Wednesday a $1.3 billion aid package for Ukraine that includes unmanned aerial vehicles and air defense missile systems.

        The package includes 4 advanced NASAMS surface-to-air missile systems, which are medium-range missiles that have already helped Ukraine counter Russian missiles, and drones, which are the missiles used to protect Washington and the surrounding area.

US Secretary of Defense Lloyd Austin said last November that the system had a 100% success rate in intercepting Russian attacks.

The package also includes the Phoenix Ghost and Switchblade attack drones, as well as anti-drone gear.

The latest package falls under the Ukraine Security Assistance Initiative (USAI), which is part of the United States' long-term commitment to assist Ukraine.

"We are determined to support Ukraine's struggle for freedom for as long as it takes," Austin said, Tuesday, after an international meeting of countries providing aid to Ukraine.

Ukraine's large aid package comes during an ongoing counteroffensive, which is facing stiff Russian resistance, slowing its progress.

According to US officials, the US is also expected to announce a separate aid package of about $400 million that includes more NASAMS units, as well as ammunition for the Patriot missile defense systems and the HIMARS missile system.

The package will also contain more artillery ammunition, which officials have warned will be in short supply, especially with the prospect of a protracted Ukrainian offensive that would deplete existing stocks.

In addition, the package includes anti-tank and anti-tank weapons such as Javelins and TOW missiles, the officials said.

Officials warned that the package was not finalized yet and could change and one official said it could be announced this week.

It should be noted that the package is not expected to include more controversial cluster bombs, the officials said, which the US provided for the first time in the previous package announced earlier this month.

And the Joe Biden administration decided to provide cluster bombs, to meet the Ukrainian need for more artillery ammunition as the United States and other countries intensify ammunition production.

For his part, Ukrainian President Volodymyr Zelensky thanked the United States and the American president for the aid package.

“Thank you for the powerful new package including anti-aircraft missile systems, artillery shells, mine clearance equipment, and other much-needed assistance that will save Ukrainian lives and bring our common victory closer,” Zelensky said on Twitter. “We appreciate the unwavering support of the friendly American people.”