More than 20 countries have accepted an invitation to attend a Ukraine-focused defense talk on Tuesday hosted by the U.S., Pentagon press secretary John Kirby said Friday.

More than 40 NATO and non-NATO countries have been invited to the talks, which will be hosted by U.S. Defense Secretary Lloyd Austin at Ramstein Air Base in Germany, Kirby said.

"The goal is to bring together stakeholders from all around the world for a series of meetings on the latest [Ukrainian] defense needs and … ensuring that Ukraine’s enduring security and sovereignty over the long-term is respected and developed,” Kirby said.

-ABC News' Somayeh Malekian

United Nations Secretary-General António Guterres will meet with Russian President Vladimir Putin and Russian Foreign Minister Sergey Lavrov in Moscow on Monday.

Guterres wrote separate letters to Putin and Ukrainian President Volodymyr Zelenskyy on Tuesday asking to meet "to discuss urgent steps to bring about peace in Ukraine," a U.N. spokesperson said earlier this week.

The international swimming federation FINA said it has suspended swimmer Evgeny Rylov, a Russian Olympic gold medalist, for allegedly attending a March concert where Russian President Vladimir Putin justified the invasion of Ukraine. The suspension will last nine months.

FINA also said Russian and Belarusian athletes and officials won't be invited to any FINA events through the end of 2022.

-ABC News' Christine Theodorou

European Council President Charles Michel and Russian President Vladimir Putin had a call Friday. Michel said afterwards on Twitter that he "strongly urged for immediate humanitarian access and safe passage from Mariupol and other besieged cities all the more on the occasion of Orthodox Easter."

Michel also said he "firmly reiterated" the EU's support for Ukraine and "condemnation and sanctions for Russia’s aggression."

According to the Kremlin's readout of the call, Michel asked Putin to have direct contact with Ukraine President Volodymyr Zelenskyy. The Kremlin said Putin "reaffirmed the well-known position on this matter, noting that such a possibility depends, in particular, on concrete results in the ongoing negotiations between Russian and Ukrainian representatives, during which the Ukrainian side is showing inconsistency and is not ready to seek mutually acceptable solutions."

White House national security advisor Jake Sullivan hinted Thursday of more sanctions coming against Russia in the "next week or two" aimed at targeting ways Moscow is evading sanctions already imposed.

“Where our focus will be over the course of the coming days is on evasion,” Sullivan said Thursday at the Economic Club of Washington. “As Russia tries to adjust to the fact that it’s under this massive economic pressure, what steps do they take to try to evade our sanctions and how do we crack down on that? And I think we'll have some announcements in the next week or two that identify targets that are trying to facilitate that evasion both inside Russia and beyond."

When Sullivan was asked whether sanctions will automatically be lifted if a negotiated peace deal between Russia and Ukraine is worked out, he appeared cautious with his words, saying, “a lot of that depends on what the shape and scope” of the agreement is.

“A lot of it depends on what the Ukrainians, in consultation with us and the Europeans come to agree to," Sullivan said. "You know, we're not going to do a deal over the head of the Ukrainians where we give a bunch of sanctions relief to Russia. But if some measure of sanctions relief were built in to some credible diplomatic solution led by the Ukrainians, that's something that we would happily discuss."

But Sullivan said Russian oligarchs shouldn't expect to ever get back their yachts and other assets seized under sanctions that have been imposed, saying the ultimate goal is "not to give them back” once the war is over.

“The president is actively looking at how we can deal with the fact that as we seize these assets, our goal is not to give them back. Our goal is to put them to a better use than that," Sullivan said. "But I'll be careful in what I say today because there's an ongoing kind of policy process around how we end up dealing with that question. But, rest assured, that the goal is not just to sit on them for a while."

-ABC News' Justin Gomez