Russia-Ukraine updates: Putin suspends key US-Russia nuclear treaty in speech denouncing West

The Russian Defense Ministry announced that Russia is suspending its participation in the execution of agreements on the export of grain from Ukrainian ports, according to Russian news agency Interfax.

"The Russian side suspends participation in the implementation of agreements on the export of agricultural products from Ukrainian ports," the Russian Defense Ministry said on Saturday.

The decision was made "taking into account the terrorist act carried out on October 29 this year by the Kyiv regime with the participation of British specialists against ships of the Black Sea Fleet and civilian vessels involved in ensuring the security of the" grain corridor ."

-ABC News' Anastasia Bagaeva

The U.S. has officially announced another $275 million aid package for Ukraine, Secretary of State Antony Blinken announced Friday.

The aid includes “additional arms, munitions, and equipment from U.S. Department of Defense inventories.”

Since the start of the conflict, the administration has provided $18.5 billion in assistance to Ukraine.

-ABC News' Shannon Crawford

Russian Minister of Defense Sergei Shoigu announced that the partial mobilization of Russian citizens for the war in Ukraine is complete, reporting that 300,000 men in total have been mobilized.

Of those mobilized, 82,000 have been sent to Ukraine, while 218,000 are being trained, Shoigu said as he met with Russian President Vladimir Putin Thursday.

"We concluded the sending citizens who were called up as part of mobilization today; notification of citizens has ended, and no additional assignments are planned," Shoigu said.

At the meeting, Putin urged the modernization of parts of the Russian military structure, according to Russian news agency Interfax.

-ABC News' Anastasia Bagaeva and Tanya Stukalova

After some stunning successes over the summer, it appears that the Ukrainian army is now facing a much tougher fight on multiple fronts in the east and south. Sviatoslav Yurash, Ukraine's youngest lawmaker, told ABC News Ukrainian forces are "seeing casualties mount up."

"The reality is dire," he told ABC News in an interview in Kyiv. "We are facing an onslaught of unparalleled proportions."

Yurash, who is fighting in the military, recently returned from what he called "hell-like" conditions in the eastern Donbas.

"The reality is an artillery barrage day in, day out, night in, night out," Yuras said.

Yurash said that Ukrainian troops still "lack" equipment.

Referring to U.S. support, he said, "nothing is enough, and everything is very welcome," pointing out that the Ukrainians are fighting along 600 miles of front lines. Weapons systems such as the U.S.-supplied Howitzers and HIMARS are prioritized to particular points of the conflict zone.

He said additional support from the West is "desperately needed."

-ABC News' Tom Burridge