US politician Nancy Pelosi spoke for a little more than eight hours in the House of Representatives to oppose the budget deal to lift spending caps and avert a government shutdown because the plan does not address immigration issues.
The House Historian's office told CNN that Pelosi's speech on Wednesday was the longest on record on the House floor.
The House Minority Leader started speaking shortly after 10 a.m., and wrapped the speech a little after 6.10 p.m.
"I have had the privilege of reading the testimony from Dreamers, I still have more," she said, receiving applause in the chamber. "I thank all of you."
A source close to the California Democrat told CNN that she thought of the idea overnight to speak for hours on the House floor.
She was wearing four-inch-heels while delivering the speech and only sipped water, the source said.
The budget deal, which was proposed by Senate leaders on Wednesday, will require Democratic support to pass the House, so the House Democratic leader's comments make the plan's future unclear.
Pelosi said she opposed that the spending deal because it does not include a permanent solution for undocumented immigrants affected by the Deferred Action for Childhood Arrivals (DACA) programme.
Pelosi has been sharing statements from DACA recipients about themselves and their successes in the US.
"We have to be strong as a country ... to respect the aspirations of people who are our future," the leader said on the House floor.
"The young people are our future and these dreamers are part of that. They've been enriched ... by the greatness of our country.
"Our plea to the speaker is for us, for ourselves, to honour the values of our founders," she continued.
House Democrats will likely spend the next 24 hours pushing to get a commitment from House Speaker Paul Ryan on floor consideration of DACA bills.
Before Pelosi's Wednesday speech, the longest floor remarks from a leader came from then-House Republican Leader John Boehner in 2009 speaking against the Democrats' cap and trade legislation, reports CNN.
Boehner's roughly one hour speech was dubbed a "fila-Boehner". He took to the floor to make a political point because as the minority leader he had little power to hold up the legislation he opposed.
There are no filibusters under House rules, but top leaders are allowed unlimited "leader time".