President Donald Trump and White House officials proposed in recent months releasing immigrant detainees into the streets of so-called “sanctuary cities,” places where local governments have decided to limit cooperation with federal immigration authorities working to locate and deport undocumented immigrants, according to officials from the Department of Homeland Security and the White House.

The plan, which was first reported by The Washington Post, would have targeted cities — many of them led or represented by Democratic lawmakers– which have policies that limit their cooperation with U.S. Immigration and Customs Enforcement.

The term sanctuary city has been used in reference to a number of policies in different jurisdictions and does not have one legal definition. There are dozens of so-called sanctuary cities across the United States, including places like San Francisco, New York City, and Denver, where Democratic leaders have been outspoken in opposing the Trump administration’s immigration policies.

When asked about the plan Thursday night, a White House official and a spokesperson from the Department of Homeland Security emailed the PBS NewsHour nearly identical statements. The White House statement said, “This was just a suggestion that was floated and rejected, which ended any further discussion.”

But Friday, Trump said the idea was still being considered. “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 wrote on Twitter. In a second tweet, he added: “The Radical Left always seems to have an Open Borders, Open Arms policy – so this should make them very happy!”

In recent years, the number of immigrants detained by Immigration and Customs Enforcement has hit record highs, with nearly 50,000 immigrants detained this year. It is not clear how many people the White House proposed releasing into sanctuary cities, but news of the proposal comes as Trump doubles down on his hardline immigration policies through personnel changes and new policy proposals.

In the past, the Trump administration tried to withhold federal funds from jurisdictions considered sanctuary cities but the effort has largely been blocked by court decisions.

Trump has also repeatedly blasted the idea of sanctuary cities. “I don’t think we like sanctuary cities up here,” Trump said during a rally in Nevada last year. “By the way, a lot of people in California don’t want them, either. They’re rioting now. They want to get out of their sanctuary cities.”

Ashley Etienne, the communications director for Pelosi, pointedly criticized the plan Thursday. “The extent of this Administration’s cynicism and cruelty cannot be overstated,” she said in a statement. “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.”

News of the president’s plan to release detainees comes amid major changes in the administration’s immigration leadership positions. On Sunday, Department of Homeland Security Secretary Kirstjen Nielsen was forced to resign from her post. Acting Deputy Homeland Security Secretary Claire Grady also offered the president her resignation this week.

Kevin McAleenan, the current U.S. Customs and Border Protection Commissioner, will become acting Secretary for the Department of Homeland Security, a move Trump announced on Twitter. On Thursday, Ronald Vitiello, the acting director of Immigration and Customs Enforcement, also announced he would be replaced in the acting role Friday by acting Deputy Director of Immigration and Customs Enforcement Matt Albence.

White House officials have told the NewsHour that the personnel changes come as the president reviews how to best pursue the immigration policies he prefers.

Meanwhile, Nielsen’s departure also added to the slate of Trump Cabinet officials operating with “acting” as part of their titles. They include acting White House chief of staff Mick Mulvaney, acting Interior Secretary David Bernhardt, acting Defense Secretary Patrick Shanahan, and acting Ambassador to the United Nations Jonathan Cohen.