House Democrats on Monday blasted the Trump administration over its “bizarre and unlawful” proposal to release immigrant detainees into sanctuary cities, and demanded documents from the White House and the Department of Homeland Security related to the floated policy.

The Democrats also claimed that if it were enacted, it would be solely for “political purposes.”

House Judiciary Committee Chairman Jerrold Nadler, D-N.Y.; House Oversight Committee Chairman Elijah Cummings, D-Md.; and House Homeland Security Chairman Bennie Thompson, D-Miss., penned a letter to DHS and the White House Monday requesting emails, and other communications between administration officials related to the proposal.

TRUMP DOUBLES DOWN ON PLAN TO SHIP MIGRANTS TO SANCTUARY CITIES, SAYS 'RADICAL LEFT' SHOULD BE HAPPY

“We are deeply troubled by multiple reports, recently confirmed by the President, that the Trump Administration is considering releasing detained immigrants into congressional districts represented by Democrats in a bizarre and unlawful attempt to score political points,” the chairmen wrote.

“Not only does the Administration lack the legal authority to transfer detainees in this manner, it is shocking that the President and senior Administration officials are even considering manipulating release decisions for purely political reasons,” they continued.

The chairmen requested communications, emails, and other documents related to the transfer or release of immigrant detainees to specific areas in the U.S.; between DHS officials and Immigration and Customs Enforcement (ICE) officials, and any other materials related to the proposed policy.

The letter comes after President Trump responded to a Washington Post report last week, all but confirming that the administration proposed releasing detained immigrants in sanctuary cities. The president said that relocating illegal immigrants to these districts should make the “Radical Left” happy.

His comments came after The Post reported that the White House proposed sending the detainees to sanctuary cities twice in the last six months. The proposal was first floated in November amid reports of a large migrant caravan from Central America making its way to the southern border. The idea was again considered in February, amid the standoff with Congress over a border wall.

The Post said the plan was shot down both times, but last week, Trump signaled the proposal isn’t dead.

“Due to the fact that Democrats are unwilling to change our very dangerous immigration laws, we are indeed, as reported, giving strong considerations to placing Illegal Immigrants in Sanctuary Cities only,” Trump tweeted last week. “The Radical Left always seems to have an Open Borders, Open Arms policy—so this should make them very happy!”

Trump repeated the remarks later at the White House: "We can give them an unlimited supply...let’s see if they have open arms."

The president doubled down as Democrats fumed over the relocation idea.

“The extent of this Administration’s cynicism and cruelty cannot be overstated,” House Speaker Nancy Pelosi’s spokeswoman Ashley Etienne said in a statement Friday. “Using human beings—including little children—as pawns in their warped game to perpetuate fear and demonize immigrants is despicable, and in some cases, criminal.”

She added: “The American people have resoundingly rejected this Administration’s toxic anti-immigrant policies, and Democrats will continue to advance immigration policies that keep us safe and honor our values.”

PELOSI FUMES OVER WHITE HOUSE PLAN TO RELEASE IMMIGRANT DETAINEES IN SANCTUARY CITIES

Pelosi’s district—San Francisco—was among the sanctuary cities to which the administration considered sending detainees.

White House officials, though, stressed earlier Friday that the plan never went anywhere. A source familiar with discussions told Fox News that Democrats who advocate leniency toward illegal immigrants should work with the administration to find ways to transport those set for release, including in their states and districts.

The proposal was apparently rejected both times it came up by administration immigration agencies.

It is unclear, at this point, whether immigration agencies would now support the proposal.

Trump has repeatedly blasted sanctuary cities, which are areas where local authorities refuse to cooperate with federal immigration agencies. The cities are typically run by Democrats.

The president was also hit last week with questions over the administration’s past family separation policy at the border. Trump said they have no plans to revive the policy, amid renewed speculation about whether the practice could return amid a shake-up in staffing at the Department of Homeland Security, including the resignation of Secretary Kirstjen Nielsen.

WHITE HOUSE PROPOSED RELEASING IMMIGRANT DETAINEES INTO 'SANCTUARY CITIES' TO TARGET POLITICAL FOES: REPORT

Kevin McAleenan, who was serving as CBP commissioner, is replacing her as acting secretary.

Nielsen’s resignation last Sunday came amid an influx of migrants at the U.S.-Mexico border. Nielsen was reportedly frustrated with the difficulty of getting other departments to help deal with the growing number of families crossing the border. But administration officials told Fox News that McAleenan best fits Trump’s requirement of being the “toughest cop” on the frontier and that Nielsen had been viewed as resistant to some of the immigration measures pushed by the president and his aides.

By last Tuesday, DHS Acting Deputy Secretary Claire Grady also resigned.

And last Wednesday, Nielsen announced that ICE Acting Director Ron Vitiello would be stepping down by the end of the week.

Fox News' Kristin Brown, Matt Leach, and The Associated Press contributed to this report.