Tensions flared over Democrats’ resistance to President-elect Donald Trump’s Cabinet nominees on the eve of his inauguration, as senators traded jabs on the sidelines of his Treasury pick’s confirmation hearing and the transition team squared off from afar with the chamber’s Democratic boss.

Incoming Press Secretary Sean Spicer said at a pre-inaugural briefing Thursday there’s “no excuse” for what he called “delay tactics” in confirming Trump’s team, as Republicans push to have as many as seven nominees confirmed right away.

But Senate Minority Leader Chuck Schumer, D-N.Y., while denying they’re trying to drag out the process, said Thursday that Democrats only expect to vote Friday on Homeland Security secretary nominee John Kelly and Defense secretary nominee James Mattis.

Meanwhile, the confirmation hearing for Steve Mnuchin as Treasury secretary turned feisty as lawmakers grilled him on his banking career – and bickered over one Republican’s joke gone bad.

The former Goldman Sachs banker’s hearing got off to a shaky start when Sen. Pat Roberts, R-Kan., joked he should give ranking member Sen. Ron Wyden, D-Ore., a Valium pill for the questioning.

“Senator Wyden, I’ve got a Valium pill here that you might want to take before the second round,” Roberts said. “Just a suggestion, sir.”

Ohio Democratic Sen. Sherrod Brown butted in and fired back, saying he hopes the “comment about Valium doesn’t set the tone for 2017 in this committee.” He added, “This is just outrageous.”

After a minute of back-and-forth bickering, Wyden, the committee’s top Democrat, said that “we have many colleagues waiting.”

Roberts snapped, “Fine Ron, I’m done.”

Nearly all of the Democrats on the committee as well as one Republican, Sen. Dean Heller, took Mnuchin to task for more than three hours of questioning – then went on a break – and returned for round two.

The tone was in keeping with the tense nature of several recent Cabinet hearings, which fueled Spicer's criticism of the process on Thursday.

Wyden criticized Mnuchin over his use of a “dynasty trust” which “shields tens of millions of dollars from taxes.” He also chastised the New York banker for using a tax-exempt foundation to push for the approval of his bank’s merger.

As questioning continued, the staff for Democrats on the committee circulated a memo that claimed Mnuchin failed to initially disclose close to $100 million of his assets on disclosure documents sent to the Senate Finance Committee. The memo also claimed he forgot to mention his role as a director for an investment fund located in a tax haven.

Democrats pounced and said the omissions should disqualify Mnuchin as a suitable fit for Treasury secretary.

“The Treasury secretary ought to be somebody who works on behalf of all Americans, including those who are still waiting for the economic recovery to show up in their communities,” Wyden said. “When I look at Mr. Mnuchin’s background, it’s a stretch to find evidence he’d be that kind of Treasury secretary.”

Wyden also turned his attention to Mnuchin and accused the Wall Street banker of putting “more vulnerable people on the street faster than just about anybody else” during widespread foreclosures on homeowners across the country.

Mnuchin said that after he was nominated by Trump as Treasury secretary he had “been maligned as taking advantage of others’ hardships in order to earn a buck.”

“Nothing could be further from the truth,” he said, adding, “I was committed to loan modifications intended to stop foreclosures. I ran a ‘Loan Modification Machine.’ Whenever we could do loan modifications, we did them.”

Mnuchin told the Senate Finance Committee that his bank extended over 100,000 loan modifications to borrowers who had fallen behind in their mortgage payments.

Mnuchin said whenever possible OneWest offered loan modifications using guidelines from a variety of government programs, but "unfortunately, not all of the homes could be saved through these programs and despite my best efforts, some were sadly subject to foreclosure."

After being nominated for the Treasury job in November, Mnuchin said his bank's foreclosures reflected the fact that before he took over the failed IndyMac, it had accumulated one of the worst portfolios of bad mortgage loans "in the history of time."

A group of 10 Democratic senators led by Sen. Elizabeth Warren participated in a forum Wednesday to hear testimony from some of the people who lost their homes after Mnuchin's bank foreclosed.

"OneWest was notorious for its belligerence and for its cruelty," Warren said.

Liberal groups began airing a television ad on the foreclosures seeking to bring pressure on five Republican senators, including Sens. Chuck Grassley of Iowa and Dean Heller of Nevada, who are both members of the Finance Committee, to vote against Mnuchin.

"Steven Mnuchin, the foreclosure king, made millions by taking people's homes with no regard to anything but his own bottom line," said Stephanie Taylor, co-founder of the Progressive Change Campaign Committee, one of the groups running the ad.

But Mnuchin's supporters include Finance Committee Chairman Orrin Hatch, R-Utah. He called Mnuchin a "leader and a manager through his career, demonstrating an ability to make tough decisions and to be accountable."

Mnuchin, who as Treasury secretary would serve as the administration's chief economic spokesman, faced questions about Trump's ambitious plans to double the country's growth rate through tax cuts, reducing government regulations and boosting government spending on infrastructure projects.

The Associated Press contributed to this report.