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

Russia is deliberately delaying the passage of ships carrying grain exports under a U.N.-brokered deal, Ukrainian President Volodymyr Zelenskyy alleged in his evening address Friday.

Zelenskyy said the delay meant that Ukraine grain exports were short 3 million tons, which he said is enough to feed 10 million people.

"The enemy is doing everything to slow down our food exports ... as of today, more than 150 ships are queuing to fulfill contractual obligations on the delivery of our agricultural products," Zelenskyy said.

"This is an artificial queue. It only arose because Russia is deliberately delaying the passage of the ships," he said.

-ABC News' Jason Volack

Russian attacks have hit 30% to 40% of Ukraine's overall national power infrastructure, Ukraine's Energy Minister Herman Halushchenko told Reuters in an interview.

"We see that they targeted a number of new [facilities], but also they shelled [facilities] which had been already shelled before to destroy them absolutely," Halushchenko said.

Asked about the scale of the damage, Halushchenko said Russian attacks have hit at least half of Ukraine's thermal generation capacity and caused billions of dollars worth of damage.

Halushchenko said electricity imports could be one of the options Ukraine pursues to get through the crisis.

-ABC News' Jason Volack

U.S. Defense Secretary Lloyd Austin spoke with his Russian counterpart, Minister of Defense Sergey Shoygu, for the second time since the invasion of Ukraine on Friday.

"Secretary Austin emphasized the importance of maintaining lines of communication amid the ongoing war against Ukraine," the Pentagon said in a brief statement.

The first call between the two was in May and lasted an hour. Officials did not say how long the Friday call was.

-ABC News' Luis Martinez

The U.S. believes Iranians are "on the ground" in Ukraine to assist Russia with its drone operations, White House spokesman John Kirby told reporters Thursday.

"We can confirm that Russian military personnel that are based in Crimea have been piloting Iranian [drones] and using them to conduct strikes across Ukraine, including strikes against Kiev in just recent days. We assess that Iranian military personnel were on the ground in Crimea and assisted Russia in these operations," Kirby told reporters.

Kirby did not know how many Iranians are in Crimea, but said the U.S. knows it is "a relatively small number."

Kirby specified that the Iranians "have put trainers and tech support in Crimea, but it's the Russians who are doing the piloting."

“We're going to continue to vigorously enforce all U.S. sanctions on both the Russian and Iranian arms trade. We're going to make it harder for Iran to sell these weapons to Russia. We're going to help the Ukrainians have what they need to defend themselves against these threats."

-ABC News' Justin Gomez