Biden's 1st 100 days live updates: Senate passes COVID relief bill along party lines

During Biden's virtual bilateral meeting with Mexican President Andrés Manuel López Obrador, he said they would be discussing the possibility of sending doses of the COVID-19 vaccine to Mexico.

Earlier Monday, however, White House press secretary Jen Psaki said it was not something the president was considering.

"The president has made clear that he is focused on ensuring that vaccines are accessible to every American. That is our focus," she said.

This is Biden's second bilateral meeting -- held spoke with Canadian Prime Minister Justin Trudeau last week.

Biden told López Obrador that it's "not by accident" that this was his second virtual bilateral meeting. In a major shift of tone from Trump, Biden made a point of saying Mexico is an equal. His remarks sought to establish a close relationship for himself that will recognize the failures of the past but move forward together.

"There’s a long and complicated history between our nations. They haven't always been perfect neighbors with one another, but what we have seen over and over again the power and the purpose when we cooperate. And we're safer when we work together, whether it's addressing the challenges of our shared border or getting this pandemic under control," Biden said.

-ABC News' Sarah Kolinovsky

Sens. Chris Van Hollen, D-Md., and Martin Heinrich, D-N.M. wrote a letter Monday urging the Biden administration COVID response team to consider a new vaccine strategy that would prioritize first doses as the threat from variants, particularly the U.K. variant, increases.

The pair of Democratic lawmakers wrote to White House Coronavirus Response Coordinator Jeff Zients, "we encourage you to explore deploying existing second doses as first doses and rely on growing real-time inventory to cover future follow-on booster shots." 

"We are not advocating for solely a single-dose regimen," the letter said. "Rather, we believe deploying existing second doses to cover more first doses—coupled with using real-time inventory in the coming weeks to serve as boost doses—would be the most societally beneficial choice and mitigate severe illness, hospitalization, and death.”

-ABC News' Trish Turner

The Senate Judiciary Committee on Monday afternoon advanced the nomination of Merrick Garland to be the nation’s next attorney general in a bipartisan vote. On a vote of 15-7, three Republicans, Sens. Lindsey Graham, R- N.C., John Cornyn, R-Texas, and Thom Tillis, R-N.C., joined committee Democrats to favorably advance the nomination to the floor. Garland is expected to be confirmed by week’s end. 

Sen. Chuck Grassley, R-Iowa, called Garland "an honorable man" in announcing his support for the nominee, but he expressed "concerns about the direction of the Department of Justice."

In the previous administration, Democrats repeatedly accused former Attorney General Bill Barr of being a partisan lawyer bent on protecting his boss, President Donald Trump, rather than enforcing the nation’s laws. Republicans, for their part, now see the potential for the Biden Justice Department becoming partisan, repeatedly voicing concerns that special counsel John Durham, appointed during the Trump administration, will not be permitted to finish his investigation into the origins of the probe into Russian interference in the 2016 election. 

"I don't have any information about the investigation. As I sit here today and another one of the very first things I'm going to have to do to speak with Mister Durham and speak about how his investigation is going. I understand he has been permitted to remain in his position, and sitting here today, I have no reason to think that that was not the correct decision," Garland said last week. "I don't have any reason to think that he should not remain in place."

Grassley said he was putting Garland "on notice" that "any actions taken to end and cover up or otherwise undermine the Durham investigation should be interpreted as premeditated and political if Durham is sidelined." 

"His career of faithful public service that I think means I owe him a chance to just do exactly what he said, but he has his work cut out for him," Grassley said of Garland’s promise to "follow the law, nothing more and nothing less." 

It was an abrupt turn of fate, given that Republicans, including Graham, Grassley, and Cornyn, sunk Garland's nomination to the Supreme Court under former President Barack Obama.

-ABC News' Trish Turner and Alexander Mallin

Sen. Joe Manchin, D-W.Va., is one of nine senators participating in a virtual meeting with Biden early Monday afternoon. Manchin, a moderate Democrat, has become a powerful vote in the 50-50 split Senate.

In the president's big push for the Senate to pass his COVID-19 relief bill, Manchin's support is vital to winning passage. Manchin and Sen. Kyrsten Sinema, D-Ariz., have already been publicly critical of the administration's push to add a $15 minimum wage increase to the bill.