Sitting down in the Oval Office with 11 Democratic Senate leaders Wednesday morning, President Joe Biden sounded confident.

“We’ll get Republican support,” he said of negotiations over his $1.9 trillion COVID-19 relief bill. “I think we’ll get some Republicans.”

The self-assured tone in Biden’s public comments belies the contentious nature of the negotiations, as some of the Democrats meeting with Biden continue to push ahead on preparing a budgetary tool to pass the measure without any Republican support on Capitol Hill.

After the meeting, Senate Majority Leader Chuck Schumer also attempted to highlight cooperation across the aisle, but left room to indicate he is still willing to forge ahead without any GOP votes.

“We’re going to all work together with this president, we are united as one, for a big bold package, working with our Republican friends, when we can,” Schumer said.

“We hope our Republican colleagues will join us in that — in that big, bold program that America needs. The vast majority of Republican voters support large parts of the program. We want to do it bipartisan, but we must be strong. We cannot dawdle, we cannot delay, we cannot dilute, because the troubles that this nation has and the opportunities that we can bring them are so large,” he continued.

The commitment to move forward was underscored Wednesday night as House Democrats voted to approve a budget resolution that would allow the chamber to advance a coronavirus relief package through the reconciliation process, which would allow Democrats in the Senate to pass the measure on a party line vote.

Emerging as a particular sticking point in the talks is the size of direct relief payments. Dialing in to the weekly House Democratic Caucus meeting, Biden suggested he’s not willing to budge on $1,400 payments, but would consider restricting the payments for lower-income Americans.

“We can’t walk away from additional $1,400 in direct checks we proposed because people need, and frankly, they’ve been promised it. Maybe we can, I think, we can better target that number. I’m okay with that. But we’re going to start my — I’m not going to start my administration by breaking a promise to the American people,” Biden said on the call.

Earlier Wednesday morning, Biden hosted his fellow Delawareans, Sens. Chris Coons and Tom Carper, in the Oval Office. Following the hour-long meeting, Coons relayed that the president would continue to move forward with negotiations on policy, but would stand firm on his promise to deliver the stimulus to working families.

“We did have a conversation about the direct payments and how those might be modified in a way to ensure that they are targeted, but President Biden was clear with us and our caucus yesterday, he’s not going to forget the middle class,” Coons said. “He’s not going to walk back from a commitment made not just to Georgia, but nationally to deliver targeted relief to those Americans most in need.”

Coons added his personal view that aid to state and local government could be a dealbreaker. Biden’s plan calls for $350 billion for state and local governments, but Republicans cut the fund from their counteroffer.

“Speaking for myself, if there is zero for state and local aid, I think that’s a non-starter. I’ve spoken with several Republican colleagues about on what terms are they willing to increase the amount significantly for some state and local aid,” Coons said.

Biden’s comments give some shape to the negotiations that the White House has revealed little on. During a press briefing Wednesday, White House press secretary Jen Psaki also pointed to funding for small businesses and local and state funding as other areas of possible cooperation, in addition to targeting the relief.

A nearly two-hour meeting with Republican senators on their $600 billion counter-proposal on COVID-19 relief in the Oval Office Monday night left both parties feeling optimistic about negotiations, but did not result in any tangible progress.

“I wouldn’t say that we came together on a package tonight. No one expected that in a two hour meeting. But what we did agree to do is to follow up and talk further at the staff level and amongst ourselves and with the president and vice president on how we can continue to work together on this very important issue,” said Sen. Susan Collins, R-Maine.

On Wednesday, Sen. Mitt Romney, one of the 10 senators who met with Biden Monday, said real changes would need to happen to get members of the party on board.

“If President Biden works with Republicans, and we make some modifications to his plan, it’s entirely possible that there would be some Republican support. But if it goes forward without any changes from what was originally proposed, I would predict that not a single Republican will support the $1.9 trillion plan,” Romney told reporters on Capitol Hill.

“I think the biggest gap between the president’s proposal, and the Republican proposal relates to $360 billion or so going to states and localities, the most recent report shows that the average state in America only lost one-tenth of 1% of revenue in 2020 compared to 2019. So that kind of number just makes no sense at all,” he said, adding that there were also “big gaps” when it came to the direct payments as well.

It’s not just Republicans posing an issue to Biden.

One key Democratic senator, Joe Manchin of West Virginia, did not participate in Wednesday’s meetings since only heads of committees involved in the budget reconciliation process were invited. The most moderate Democrat in the Senate, Manchin has expressed displeasure with the $1,400 payments and said he feels Biden’s plan includes too much state and local government aid. The White House is dependent on Manchin’s cooperation to pass a bill via reconciliation given the 50-50 split in the Senate and Manchin has said he wants the process to be bipartisan, though he did support a procedural vote to continue the reconciliation process Tuesday.

“I want it to be bipartisan. If they think we’re going to throw all caution to the wind and just shove it down people’s throats — that’s not going to happen,” he told reporters on Capitol Hill.

For Biden, who campaigned on the promise of delivering bipartisan legislation as president, coronavirus relief is proving to be a challenging first test. While the president has stressed his preference for both parties to support the measure, Coons warned Biden would not allow relief to be delayed, adding that he was committed to delivering help to those in need in “weeks, not months.”

ABC News’ Trish Turner contributed to this report.