WASHINGTON — The Trump administration on Wednesday unveiled a series of aggressive changes to the legal immigration system, including ending a temporary residency permit for millions of people here illegally, sharply cutting the number of refugees who can resettle in the United States, and slashing a host of other immigration programs that have extended the life of people who had either arrived in the United States illegally or overstayed their visas.
Most of the restrictions would apply only to people outside the United States at the time of enactment. But if the administration achieves its goal of drastically cutting future immigration numbers, it will also have an immediate effect on those already in the United States who are here legally, and people on visas, by reducing the number of available visas under categories like family, employer-based and student.
The sweeping policy changes, most of them for people here legally or who have come into the United States legally, put President Trump at odds with business leaders who have sought less restrictive immigration policies. They also put him at odds with the immigration lawyers, faith leaders and others who have pleaded with the White House not to end the program known as DACA, which has allowed roughly 700,000 young adults brought illegally into the United States as children to live and work here without fear of deportation.
The Trump administration’s announcement on Wednesday reflected a decision-making process that included political considerations, including a midterm election looming next week.
Officials from Immigration and Customs Enforcement, which plays a major role in deporting people, were also wary of the negative effect the actions could have on immigrant communities that have long supported the president and might have angered by the news.
In the end, it appears, the White House got some of what it wanted.
Many of the immigration restrictions were the centerpiece of a bill that passed the House in May. Speaker Paul D. Ryan (R-Wis.) said at the time that he would prefer that the Trump administration make such changes without legislation.
“We all agree on what kind of enforcement-only reforms will secure our borders and keep Americans safe,” Ryan said. “Enforcing existing law is not amnesty. Amnesty is the forgiveness of a debt after it is due. We are not talking about debt here. These are law-abiding immigrants who work hard and do the right thing.”
The White House and Republican allies in Congress are eager to cut the current legal immigration program — and the Democrats and advocacy groups want a more robust overhaul.
President Trump and his advisers on Wednesday expressed sympathy for people who were brought to the United States illegally as children.
“We have compassion for DACA recipients and their families,” Mr. Trump said.
But the president said that he would sign an executive order halting DACA in six months, paving the way for Congress to consider a legislative fix. He said that if Congress does not act, he would begin deporting 2,000 to 3,000 DACA recipients each day, until a legislative solution is passed.
Mr. Trump said in an interview broadcast on Wednesday on Fox News that he was working with a bipartisan group of legislators on comprehensive immigration legislation and said he hoped to receive support from the Democrats.
“The Republicans don’t have the votes to get this done, in my opinion,” he said.
But Democrats who have worked with Mr. Trump on immigration matters described the proposed legislation as the same type of harsh immigration restrictions that they argue have undermined President Barack Obama’s efforts to broaden the immigrant ranks through executive actions.
When asked about how Mr. Trump’s move on DACA and other initiatives would play with voters, Mr. Ryan said he “can’t overstate the support I have for the rule of law and for those Dreamers and for the cause of immigration reform.”
“The vast majority of immigrants are not criminals or people who pose a public safety threat, but are hardworking individuals who pursue their dreams in America,” he said. “We have some very generous rules as it relates to being able to enter this country legally.”
Senate Minority Leader Charles E. Schumer of New York said Mr. Trump’s order on DACA will “devastate” the immigrant communities that it was supposed to help.
The immigration plan under discussion in the House is based on the so-called “Bacon-Thomas” bill, which would tighten borders by cutting asylum programs and cutting annual quotas for certain types of immigrants.
The legislation would set up a point system that would give preferential treatment to people who have higher-paying jobs, and others who have skills that are in short supply, such as graduate degrees. But the bill would eliminate opportunities for people with family members in the United States and for people who are seeking a future in fields like science, technology, engineering and mathematics, or STEM.
The plan being advanced by the White House would give priority to a narrower range of immigrants. It would give preference to those with high-level skills or who earn $1 million or more a year. And it would also set up a point system, known as a “merit-based” system, for some types of family immigrants and refugees.
The Trump administration, however, is not backing down from its vow to end the DACA program, which has provided quasi-legal status for nearly 800,000 people.
Mr. Trump initially gave Congress until early March to take action on the immigration status of DACA recipients. But he said Wednesday that he would keep that deadline, a year and a half from now, and that he expected Congress to act before then.
The announcement on Wednesday was a major setback for the four Democratic senators who have been negotiating with the White House.
Under the plan that he outlined on Tuesday, Mr. Trump said he would continue to give Dreamers protection from deportation and would also expand immigration. But he said the new program would help people who arrived in the United States in the past 15 years, though many have lived in this country for more than a decade.
About 1.2 million people would be given the opportunity to remain in the country legally and get a reprieve from deportation for two years, including 1.1 million who were brought to the United States illegally and 690,000 who are in the country under temporary protected status.
He said that more than 180,000 Haitians in the United States on temporary protected status would have their status terminated, even if they had not requested it.
The American Immigration Lawyers Association denounced the plan as an attempt by the administration to “score political points at the expense of the livelihoods and well-being of hundreds of thousands of individuals across the country.”
Democrats on Capitol Hill were equally critical of the proposal.
Senator Claire McCaskill, Democrat of Missouri, who is facing a re-election battle, said that voters would reject such proposals in Congress. “This is a cynical and heartless attempt by President Trump to distract from his monumental failures and lack of accomplishments
