Biden-Putin summit highlights: 'I did what I came to do,' Biden said

Putin indicated on Friday that he'd be willing to talk about a potential "prisoner swap" between two U.S. Marine veterans, Trevor Reed and Paul Whelan, for Russians being held in the U.S.

Russian officials have indicated they would like to trade Reed and Whelan for two Russians held in the U.S.: Viktor Bout -- one of the world's most notorious arms dealers and dubbed "the Merchant of Death" — and also Konstantin Yaroshenko, a pilot currently serving a lengthy jail sentence for a drug smuggling conviction.

David Whelan told ABC News Live Prime anchor Linsey Davis on Tuesday that his brother, who is manufacturing clothes in a Russian labor camp, is a hostage and that it's difficult to know when that might come to an end.

"I'm always hopeful that he'll be released, but I don't have any idea what the timeline might be," David Whelan said. "The Biden administration has been very outspoken about Paul's case and we've appreciated that as a family. It's given us hope and it's given him hope."

"But he's still a hostage and there's no evidence yet that the Russians are willing to exchange in any exchange for him," David Whelan continued. "They said last week -- the Russian government did — that they would not consider Paul for exchange."

Whelan's family released an audio message from him on Monday recorded from the prison camp in central Russia where he is held. In it, he appealed to Biden to help free him.

"Please bring me home to my family and my dog Flora where I belong. Thank you, Mr. President, for your commitment to returning me home and bringing this deplorable hostage situation to an expedient conclusion," Whelan said in the recording that his family said was made on May 30.

-ABC News' Haley Yamada and Patrick Reevell

Ahead of Wednesday's summit in Switzerland, both leaders agreed that it is a "low point" between the U.S. and Russia relationship

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Biden to hold high-stakes summit with Putin on Wednesday

Both leaders agreed that it is a “low point” between the U.S. and Russia relationship. President Joe Biden will meet with Russian President Vladimir Putin in Geneva, Switzerland, to discuss relations.

ABCNews.com

Ahead of the summit, ABC News Chief Global Affairs Correspondent Martha Raddatz said Biden needs to walk a fine line in an effort not to alienate Putin.

"He wants the relationship to be better — the U.S.-Russia relationship — to be better than it has been," Raddatz said on ABC News Live Prime Tuesday. "And they both agree that it's at one of the lowest points in history."

"So, President Biden will have to give his grievances to Putin, telling him what he wants to do — and yet, we even heard a bit of that today, a little flattery, a little, you know, he is a 'tough guy,' he is a 'bright guy,' President Putin, and he is a 'worthy adversary,'" Raddatz continued. "That is diplomacy 101."

In a separate interview with ABC News' Linsey Davis, Masha Gessen, a staff writer at the New Yorker and author of "Surviving Autocracy," agreed that "Russian-American relations are at an all time low."

"Biden is faced with an incredibly difficult challenge," Gessen added.

Watch the interview:

Amid all the high-level shadow boxing setting up President Joe Biden's summit with Russian President Vladimir Putin, Biden has added a new wrinkle -- one that amounts to a test for himself that awaits him back home.

Biden has cast this moment in the world community in broad terms for the United States -- a chance to assert the power of democratic nations in the face of challenges from China and Russia in particular. Asked Monday what he is telling allies who may be worried about any American slide toward autocracy, Biden again went big.

"What I'm saying to them is, watch me," Biden said. "That's why it's so important that I succeed in my agenda."

Biden was nonchalant in his condemnation of what he called the "phony populism" of former President Donald Trump. Speaking about Republicans, he flatly observed that "the Trump wing of the party is the bulk of the party, but it makes up a significant minority of the American people."

Still, just hours earlier, Senate Minority Leader Mitch McConnell served notice that his brand of hardball is still going to be played, with a warning about what Republican Senate control would mean for any Supreme Court vacancy under a Democratic presidency.

McConnell is objecting to congressional scrutiny of Trump-era Justice Department strategies, just like he did to the proposed Jan. 6 commission. And it's still far from clear whether any infrastructure or climate-change legislation can pass with Republican support, to say nothing of the prospects for tax reform.

Asked about Putin's laughing response to Biden's assertion that he is a killer, Biden said his message back would be that he is laughing as well. The world now is watching -- and will still be when Biden and Putin are both back home.

-ABC News Political Director Rick Klein