The Wagner Group's chief Yevgeny Prigozhin said he has ordered his mercenaries to halt their march on Moscow and return to their field camps, saying he wants to avoid shedding Russian blood.

Prigozhin made the announcement in an audio message posted on his Telegram channel.

Russian state media has shown Wagner fighters packing up and reportedly leaving Rostov.

Russian President Vladimir Putin has called Belarusian President Alexander Lukashenko and thanked him for his efforts de-escalating the situation.

-ABC News' Patrick Reevell and Tomek Rolski

Gen. Mark Milley, the chairman of the Joint Chiefs of Staff, has canceled his planned trip to Israel and Jordan due to the situation in Russia. The trip was to have begun Saturday.

Milley also spoke with his Ukrainian counterpart, Commander-in-Chief of the Ukrainian Armed Forces Gen. Valerii Zaluzhnyi.

"They discussed the unprovoked and ongoing Russian invasion of Ukraine and exchanged perspectives and assessments. The Chairman reaffirmed unwavering support for Ukraine’s sovereignty and territorial integrity," according to Joint Staff spokesperson Col. Dave Butler.

The Pentagon said Department of Defense Secretary Lloyd Austin is monitoring the ongoing situation in Russia and will continue to be briefed on any significant developments.

-ABC News' Luis Martinez

Andrey Vorobyov, the governor of the Moscow region, has suspended mass events outdoors and at educational institutions until July 1.

Moscow Mayor Sergey Sobyanin urged residents to refrain from traveling around the city. Monday was also declared a non-working day for the city. Sobyanin said that a counter-terrorism regime was declared in Moscow and that the situation was difficult.

-ABC News' Tomek Rolski

President Joe Biden spoke with French President Emmanuel Macron, German Chancellor Olaf Scholz and U.K. Prime Minister Rishi Sunak about the developments in Russia.

Biden and Vice President Kamala Harris were also briefed by their national security team on the developments in Russia and will continue to receive updates throughout the day, the White House said Saturday.

-ABC News' Justin Gomez

The United States "is prepared to defend every inch of NATO territory," National Security Advisor Jake Sullivan said Wednesday, amid Russia's threats of military retaliation if Sweden and Ukraine officially join the alliance.

"At the end of the day, Russia does not get a vote in who joins NATO," Sullivan told ABC News' George Stephanopoulos during an interview Wednesday on "Good Morning America."

"If Russia does choose to test Article 5, President Biden has said he is prepared to defend every inch of NATO territory," he added. "And later tonight, when he addresses a large crowd in Vilnius in a speech about his vision for Euro-Atlantic security and for American leadership, he will reinforce this point about the sanctity of Article 5."

Article 5 of the NATO treaty states that the signed parties "agree that an armed attack against one or more of them in Europe or North America shall be considered an attack against them all."

Sweden and Finland, which have historically embraced neutrality, applied for NATO membership together last year despite warnings from Moscow against doing so, as Russian forces invaded Ukraine. Finland officially joined the alliance in April following Turkish ratification, but Turkey and Hungary have yet to ratify Sweden’s membership. NATO Secretary-General Jens Stoltenberg announced Monday that Turkish President Recep Tayyip Erdogan has agreed to send Sweden’s NATO accession documents to Turkey’s Parliament for approval "as soon as possible," one of the last steps in the membership process.

Meanwhile, Ukraine is pushing hard for NATO membership as Russia’s war presses on. Stoltenberg announced Tuesday that the bloc "will issue an invitation for Ukraine to join NATO when allies agree and conditions are met," pledging to speed up the process by eliminating bureaucratic hurdles, but without offering a timeline.

"All 31 allies got together yesterday to say with one voice that Ukraine's future is in NATO. The real question is just how we work down the pathway to get them in," Sullivan told ABC News on Wednesday. "So the signal that NATO sent yesterday was very positive to Ukraine about its future prospects for joining NATO, and we will work in terms of the democratic and security sector reforms that are necessary. And in the meantime, we're not just going to sit around. We're going to provide Ukraine with the weapons and military assistance it needs to defend its territory against Russia and to deter future aggression from Russia."

Ukraine has requested F-16 fighter jets and long-range missiles to aid its counteroffensive against Russian forces. Sullivan said the U.S. has already taken steps with NATO allies to begin the training of Ukrainian pilots on F-16s, which "will take some time," and then the aircraft will be transferred to Ukraine "likely from European countries that have excess F-16 supplies." As for the long-range missiles, Sullivan said the U.S. will continue to look into the issue and discuss it with Ukraine.