Russian Foreign Minister Sergey Lavrov "diverted" U.S. Secretary of State Antony Blinken's calls to reconsider the decision to suspend Russia's participation in the New START treaty, Russia's foreign ministry told Interfax, Russian news agency.

“If they want to return to diplomacy, let them return. If they are engaged in self-promotion and such inexpensive PR, well, this is possible. True, the result will be appropriate," Maria Zakharova, a spokesperson for the ministry, told Russian TV channel Rossiya-1.

-ABC News' Natalia Shumskaia

U.S. Secretary of State Antony Blinken and Russian Foreign Minister Sergey Lavrov had an "on the go" talk during the G-20 Meeting of Foreign Ministers in India, but there were no negotiations, Russian Foreign Ministry spokeswoman Maria Zakharova told TASS, a Russian news agency, Thursday.

"Blinken asked for a contact with Lavrov. Sergey Viktorovich [Lavrov] had communication on the go during the second session. But there were no negotiations, no meeting or so on," the diplomat said.

Blinken had said earlier in the day during a press conference he had "spoke briefly" with Lavrov and discussed ending the war, as well as Russia rejoining the New START Treaty on nuclear arms.

"I told the foreign minister what I and so many others said last week at the United Nations and what so many G-20 foreign ministers said today: End this war of aggression, engage in meaningful diplomacy that could produce a just and durable peace," he said. "The United States stands ready to support Ukraine through diplomacy to end the war on this basis."

A senior State Department official downplayed any hopes that the conversation moved the needle on any of the topics.

-ABC News' Tanya Stukalova and Shannon Crawford

Ukraine has shot down 80% of Russian missiles, according to Commander of the Joint Forces of the Ukrainian Air Force Serhiy Nayev.

Nayev made the assessment in a Facebook post on Wednesday about the effectiveness of the air defense system.

"The enemy is also changing his tactics and ways of using air strike means, so we test after every hit," he wrote. "This analysis proves that commanders, respectively, make decisions that ensure the durability of the air defense is at the highest level."

-ABC News' Ellie Kaufman

Colonel-General Oleksandr Syrsky, the commander of Ukraine's Eastern Group of Forces, will send additional units to Bahkmut, according to Ukraine's Deputy Defense Minister Hanna Malyar.

"Bakhmut has been the epicenter of hostilities for several months now. The enemy has concentrated its key efforts there because it aims to reach the borders of the Donetsk region. The situation there is really tense and difficult," Malyar said.

Ukrainian President Volodymyr Zelenskyy echoed that statement in his nightly address.

"The most difficult situation is still Bakhmut and the battles that are important for the defense of the city," he said.

-ABC News' Ellie Kaufman and Will Gretsky

Russian President Vladimir Putin acknowledged Russian military losses from its ongoing invasion of Ukraine during his annual meeting with the federal security service Tuesday.

"Unfortunately, comrade officers, we know that there are losses in our ranks," Putin said.

Putin called on the FSB to provide "support" to the families of soldiers who have died in the war.

"We will always remember their heroism and bravery," he added.

Putin did not say how many soldiers have died in the war and the Russian Ministry of Defense hasn't disclosed an exact number of losses since September 2022 when Defense Minister Sergey Shoigu said just shy of 6,000 troops had died.

Secretary of State Antony Blinken and other State Department officials said Russia has likely suffered 200,000 injured or dead soldiers since the start of the war.

Putin also called on the FSB to make sure its border guard "undertake special efforts to control the Russian state border with Ukraine."

A "special group" is currently deployed at the Russia-Ukraine border, made up of border agencies, the FSB air arm, the Russian Armed Forces and the Russian National Guard, according to Putin.

"Your mission is to prevent any incursions by sabotage groups and stop any attempts to smuggle weapons and ammunition into Russia," Putin told the FSB board.

-ABC News' Tanya Stukalova and Anastasia Bagaeva