Sen. Chris Van HollenChristopher (Chris) Van HollenMerkley leads Dem lawmakers to border amid migrant policy outcry Overnight Defense: Trump defends summit results | GOP chairman tries to clarify canceled war games | House panel advances 4.6B defense bill | Saudis begin Yemen offensive GOP senator fails to kill provision blocking Trump's ZTE deal MORE (D-Md.) swiped at President TrumpDonald John TrumpEx-ethics chief calls on Trump to end 'monstrous' migrant policies Laura Bush blasts Trump migrant policy as 'cruel' and 'immoral' US denies report of coalition airstrike on Syria MORE on Saturday while attending the "March for Our Lives" rally in Washington, D.C., calling for action on gun violence.

Asked about estimated attendance at the rally, which was expected to draw hundreds of thousands of people, Van Hollen told The Hill, "I can tell you for sure, it's larger than the Trump inauguration."

ADVERTISEMENT

While exact turnout figures have yet to be released, organizers obtained a permit for 500,000 people to rally in D.C. around Pennsylvania Avenue near the White House. Hundreds of similar marches were planned worldwide.

Trump sparked backlash last year after sending then-White House spokesman Sean SpicerSean Michael SpicerSanders dismisses — but doesn't deny — reports about her exit Spicer joins pro-Trump super PAC CBS: Sanders may leave White House at end of year MORE to confront members of the media over coverage of his inauguration crowd size after taking office.

Spicer claimed the press misrepresented the number of people at the inauguration after numerous reports indicated that the crowd was much smaller than former President Obama’s 2009 inauguration crowd.

The White House spokesman claimed at the time that Trump's inauguration crowd size was “the largest audience to ever witness an inauguration, period, both in person and around the globe,” garnering pushback from the media.

Spicer said in September that he regretted his fiery exchange with reporters.

— Mike Lillis contributed