President Donald Trump confirms plan under consideration to release immigrants in sanctuary cities He supports the suggestion despite DHS concerns.

President Donald Trump confirmed on Friday that his administration engaged in conversations about a plan to transfer immigrants detained at the southern border onto the streets of "sanctuary cities."

"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 The Radical Left always seems to have an Open Borders, Open Arms policy – so this should make them very happy!" the president said in a series of tweets on Friday.

At an event discussing 5G technology later on Friday, President Trump doubled down on his earlier tweets.

The president pointed to California in particular as a target destination and referred to California Governor Jerry Brown, saying "California certainly is always saying, 'oh we want more people' ...well we'll give them more people. We can give them a lot. We can give them an unlimited supply and let's see if they're so happy. They say 'we have open arms.' They're always saying they have open arms, let's see if they have open arms."

The alternative, Trump said, is for Democrats to change immigration law.

Senior-level sources familiar with the matter told ABC News that the proposal was aimed, in part, to punish political rivals by placing immigrants in their respective districts.

Prior to the president's tweet, a White House official told ABC News "This was just a suggestion that was floated and rejected, which ended any further discussion."

An official at the Department of Homeland Security had released a nearly identical statement asserting that the discussion is now over.

Sanctuary cities, such as San Francisco and New York City, do not cooperate with the federal government in complying with Immigration and Customs Enforcement (ICE) requests.

The proposal, first reported by The Washington Post, would have targeted House Speaker Nancy Pelosi’s district in San Francisco, among other Democratic strongholds, according to these officials.

"The extent of this Administration’s cynicism and cruelty cannot be overstated," said Ashley Etienne, Pelosi’s communications director.

"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."

House Speaker Nancy Pelosi commented on the reporting Friday saying the plan was "unworthy of the presidency."

“Well, I don't know anything about it but again it's just another notion that is unworthy of the presidency of the United States and disrespectful to the challenges that we face as a country as the people to address who we are as a nation of immigrants," Pelosi said.

The proposal was under discussion in November and February, according to these officials. During both of those months, President Donald Trump was aggressively seeking a political win on border issues. In November, a migrant caravan was approaching the border in the heat of the midterm elections. In February, he was involved in budget negotiations with Democrats over the border wall.

The November email contained the subject line "Sanctuary City Proposal," according to the Washington Post who reviewed the emails. “The idea has been raised by 1-2 principals that, if we are unable to build sufficient temporary housing, that caravan members be bussed to small- and mid-sized sanctuary cities,” read the email, sent by May Davis, the White House deputy policy coordinator. “There is NOT a White House decision on this.” Sources familiar with the email confirmed the Post's account of this email, but it has not been reviewed by ABC News.

A senior DHS official told ABC News that the president himself raised this directly with then-Secretary Kirstjen Nielsen. Nielsen asked the legal team to review the idea and they flatly rejected it saying it is illegal.

Trump has described sanctuary cities as “crime infested,” repeatedly asserting that these areas become hotbeds of criminal activity after employing "sanctuary" policies.

But a 2016 study from researchers at the University of Riverside disputes this broad claim.

“We find no statistically discernible difference in violent crime rate, rape, or property crime across the cities,” the study found.

Immigrants are less likely to get deported living in “sanctuary cities” compared with cities that don’t have limits on local law enforcement cooperation with ICE, according to a recent study out of Syracuse University.

The study suggests that the potential White House plan could put a burden on these localities, if implemented, it could also make it harder to deport people.

News of the White House proposal comes the same week Trump appeared to lament the loss of his child separation policy. While he refuted reports that there were discussions about bringing the policy back, he blamed the recent surge in border crossings on the fact that the policy was ended.

ABC News’ Quinn Owen and Sarah Kolinovsky contributed to this report.