Biden signs bipartisan infrastructure bill with Republicans on hand to celebrate win

After months of negotiations, a massive bipartisan infrastructure bill that promises significant investments in every pocket of the country got President Joe Biden's signature on Monday.

"My fellow Americans, today I want you to know we hear you, and we see you. The bill I'm about to sign into law is proof that, despite the cynics, Democrats and Republicans can come together and deliver results," Biden said. "We can deliver real results for real people we see in ways that really matter each and every day to each person out there. And we're taking a monumental step forward to 'Build Back Better' as a nation."

Biden was joined by a bipartisan group for the $1.2 trillion infrastructure bill signing at a White House ceremony -- marking a major victory for lawmakers from both parties who committed to working in a bipartisan way and even more so for Biden, who campaigned on a promise to work across the aisle.

"For too long, we've talked about having the best economy in the world. We've talked about asserting American leadership around the world with the best and the safest roads, railways, ports, and airports. Here in Washington, we've heard countless speeches, promises, and white papers from the experts," Biden said. "But today, we are finally getting it done. So my message to the American people is this: America is moving again. And your life is going to change for the better."

The infrastructure package, with $550 billion in new spending, will address the nation's core infrastructure needs including $110 billion for highways, roads and bridges, $66 billion for passenger rail, $65 billion in high-speed internet, $55 billion for water, $39 billion in public transit, $25 billion for airports, $7.5 billion for electric vehicle charging stations, and $17 billion for ports, among other areas.

"I truly believe that 50 years from now, historians will look back at this moment and say, that's the moment America began to win the competition of the 21st century. So with confidence, optimism, with vision and faith in each other, let's believe in possibilities. Let's believe in one another. And let's believe in America," he said to cheers and applause.

The White House said the plan will create on average 1.5 million jobs per year over the next decade.

"We got it done, America," Vice President Kamala Harris said with a smile.

Yet, what Biden hopes will be a key moment in his presidency comes amid a new ABC News/Washington Post poll showing only 41% of Americans approve of Biden's job performance while 53% disapprove. His keystone policy initiatives are far more popular than he is, with 63% support for the infrastructure bill. Just 31% say he's keeping most of his major campaign promises, and 35% think he's accomplished much overall.

Several congressional Republicans joined Democrats at the White House for the South Lawn signing ceremony, as well as GOP leaders at the state and local level. Bu in all, only about 18% of Republicans who voted for the popular legislation were in attendance -- and the entire group faces extreme criticism, and in some cases, death threats, for supporting the infrastructure package -- blowback encouraged by former President Donald Trump.

Sen. Kyrsten Sinema, D-Ariz., a leader in negotiations, spoke ahead of the president, along with House Speaker Nancy Pelosi and Senate Majority Leader Chuck Schumer.

"Our plan will create millions of jobs and make our country stronger, safer, and more globally competitive without raising taxes on everyday Americans," Sinema said to the crowd of approximately 800 guests gathered before American flags on the South Lawn, going to thank the bipartisan group of lawmakers who negotiated the deal.

"The American people want to see us coming together," said Sen. Rob Portman, R-Ohio, who led negotiations for Republicans. "They know that despite our differences we should be able to figure it out and work together to solve big problems. We can start by recognizing that finding common ground to advance the interests of the American people should be rewarded not attacked," Portman added. "This should be the beginning of a renewed effort to work together on big issues facing our country."

Senate Minority Leader Mitch McConnell, who has touted the bill in his home state of Kentucky as "good for the country," said last week he has "other things I've got to do other than go to the signing ceremony."

Biden took a moment to personally thank McConnell for voting for the bill and for "talking about how useful and important it is" and touted the bipartisan victory as one the American people wanted.

"I ran for president because the only way to move this country forward was through compromise and consensus. That's how the system works. That's American democracy. And I am going to be signing a law that is truly consequential because we made our democracy deliver for the American people," he said.

Amid the criticism also fueled by rising inflation -- in the wake of the consumer price index hitting its highest increase in three decades -- White House press secretary Jen Psaki said on Friday that the $1 trillion infrastructure bill, along with the $1.75 trillion reconciliation package still pending in Congress, will offset inflation.

"I would note that everyone from the Federal Reserve to Wall Street agree with our assessment that inflation is already expected to substantially decelerate next year," Psaki said in a press briefing. "And economists across the board also agree that the president's economic agenda … will not add to inflationary pressure and will ease inflationary pressure over the long term."

The White House has announced that former lieutenant governor of Louisiana and former New Orleans Mayor Mitch Landrieu, who helped that city recover from Hurricane Katrina, will join the Biden administration as a senior advisor and oversee the implementation of the package. Biden will also sign an executive order on Monday creating a task force to implement the package into law, which will be co-chaired by Landrieu and National Economic Council Director Brian Deese.

But Biden's plan to "Build Back Better" is not complete, which Democrats alluded to in their speeches on Monday.

Congressional Democrats still need to pass his $1.75 trillion social spending framework they plan to move through reconciliation, a lengthy budget process that would not require Republican support since Democrats hold razor-thin majorities in both chambers. That plan includes universal pre-K, funding to limit child care costs, a one-year continuation of the child tax credit expanded earlier this year, and, at the insistence of progressives and with the Speaker's support, four weeks of paid family and medical leave.

Sen. Joe Manchin, D-W.Va., key to passing the package, hasn't committed to doing so -- expressing his concerns with the cost as negotiators finalized details.

Democrats, appearing to move ahead with a new rule vote, argue that both packages will pay for themselves and are waiting for scoring from the Congressional Budget Office, expected by Friday, they hope will make their case to Manchin and other moderate House Democrats.

In the end, it took 87 days following the passage of the bipartisan infrastructure bill in the Senate to get the spending approved in the House, as well as two visits to the Capitol by the president and dozens of meetings between the White House and representatives.

Despite an uncertain fate in the Senate, Pelosi and progressives want to hold a vote on the larger social spending package this week, building off the momentum of Biden's signing Monday.

ABC News' Molly Nagle, Justin Gomez, Ben Siegel and Trish Turner contributed to this report.