Watch: Biden holds first solo press conference in the U.S. in 300 Days

President Joe Biden on Wednesday boasted about his administration's achievements one year in office, despite tanking poll numbers and rising inflation and COVID cases.

This is Biden's first solo press conference in the United States in 300 days. He has been criticized for being behind most predecessors in press conferences one year in office.

Biden touted how the fight against COVID-19 is better than one year ago. He also said he is "rebuilding America."

The President said he has a three-part plan to help Americans, which includes fixing the supply chain, passing the Build Back Better plan, and promoting competition in the marketplace.

When asked if he overpromised to the American public, Biden responded: "I didn't overpromise, but I have probably outperformed what anybody thought would happen."

He bragged, "We're in a better place than we've been, clearly better than a year ago" with COVID-19. Vaccines were not widely available one year ago. More than 1 million new COVID cases were recorded Tuesday, according to Johns Hopkins.

Biden blamed Republicans for lack of progress. "We made enormous progress, but one of the things… is get my Republican friends to get in the game of making things better in this country," Biden said.

A reporter said that Biden's "strategy isn't working," to which he responded with a chuckle and touted accomplishments. 

"I got two real big ones done. Bigger than any president has ever gotten in the first year," Biden said before laughing.

Biden warned that Russia would suffer heavy losses if they invade Ukraine.

"If they invade, they're gonna pay," Biden said, later adding, "My guess is that he [Putin] will move in." 

One Reuters reporter asked Biden: "Are you effectively giving Putin permission to make a small incursion into the country?"

Biden chuckled and said it was a good question. "I guess it did sound like that, didn't it?" he said.

He later said that Putin is "not in a very good position to dominate the world" without using nuclear power.

He also commented on the Supreme Court's decision to strike down the business vaccine mandate. "The Supreme Court decision I think was a mistake," Biden said.

When asked about how he compared Republicans who did not support him to Bull Connor and segregationists, Biden angrily said, "Go back and read what I said and tell me."

A Newsmax correspondent said to Biden: "A poll released this morning by Politico Morning Consult found 49% of registered voters disagreeing with the statement saying 'Joe Biden is mentally fit.' Not even a majority of Democrats who responded strongly reaffirmed that statement."

Biden said: "I'll let you make the judgment whether they're correct."

The reporter continued: "Why do you suppose such large segments of the American electorate have come to harbor such profound concerns about your cognitive fitness?"

"I have no idea," Biden answered.