The controversy over the size of the crowd at President Trump's inauguration spilled into a confirmation hearing for Trump's nominee for budget director Tuesday.

Sen. Jeff Merkley, D-Ore., having just arrived at the hearing breathless from walking across the Capitol complex, presented the nominee, Rep. Mick Mulvaney of South Carolina, with a poster-sized photo comparing the crowd at President Obama's 2009 inauguration with that of Trump. He then asked Mulvaney which crowd appeared to be bigger.

Mulvaney responded that the crowd at Obama's inauguration appeared to be bigger, based on the photos.

The new Trump administration sparred with the media over the weekend over the size of the crowd, claiming that Trump's audience was larger.

Merkley said he brought up the controversy at the budget-related hearing because budgets often contain "buried deceptions."

The crowd-size controversy, he said, "is an example of where the president's team, on something very simple and straightforward, wants to embrace a fantasy rather than a reality."

Merkley went on to compare past Republicans' claims that tax cuts can generate new revenue for the government to falsehoods, or "alternative facts," a reference to a statement by Trump adviser Kellyanne Conway on Sunday in relation to the administration's claims about crowd size.

"I'm deadly serious about giving you hard numbers," Mulvaney said.