Defense Secretary Lloyd Austin announced a new $6 billion weapons purchases for Ukraine on Friday that he said is the biggest so far and will purchase new weapons systems for Ukraine, including additional Patriot missiles it needs to counter Russian missile barrages on its cities.

"This is the largest security assistance package that we've committed to date," Austin said at a Pentagon news conference.

"It will include critical interceptors for Ukraine's Patriot and NASAMS air defense systems, more counter-drone systems and support equipment, significant amounts of artillery ammunition, and air to ground munitions and maintenance and sustainment support," he added.

The new aid package is the second time this week that the Pentagon has provided Ukraine with new aid from the $61 billion in aid passed earlier this week by Congress and signed by President Joe Biden.

On Wednesday, the Biden administration announced a $1 billion aid package to immediately provide Ukraine with weapons and ammunitions from existing U.S. military stockpiles.

The $6 billion aid package announced Friday falls under the Ukraine Security Assistance Initiative (USAI) that procures contracts with American companies to build weapons that will meet Ukraine's long-term security goals.

Even though the contracts are expedited, it will take some time for those weapons to get to Ukraine since they will be built from scratch.

Providing additional air defense systems for Ukraine has been a priority for the U.S. and was the focus of the monthly meeting earlier Friday of the Ukraine Defense Contact Group, the 50 nations providing weapons to Ukraine.

"We urgently need Patriot systems and missiles for them," Ukraine's President Volodymyr Zelensky told the group in a video message.

"This is what can and should save lives right now. At least seven Patriots are necessary for our cities to be safe. You have these systems and they truly can change the situation now change it for the better," he said.

"This year, Russian jets already used more than 9,000 guided aerial bombs against Ukraine and we need the ability to shoot down the air combat aircraft so that they do not approach our positions and borders," Zelenskiy said.

At his news conference, Austin repeatedly noted that the Patriot weapons systems should not be characterized as "a silver bullet" but that what was needed for Ukraine's air defense was an integrated air defense system made up of various weapons and capabilities.

Zelensky also said that the months-long delay in getting Congress to approve more U.S. military aid had given Russia the initiative on the battlefield.

"Although in a half a year while we were waiting for a decision on the American support, the Russian army managed to seize the initiative on the battlefield we can still now not only stabilize the front, but also move forward achieving our Ukrainian goals in the war," said Zelensky.

He said Ukrainian troops were at a 10-to-1 disadvantage in artillery ammunition. "You can imagine what our soldiers feel when they simply have nothing to respond to enemy fire," something he said "inspires Putin to fight on."