President Trump is demanding a long list of line immigration measures that in exchange for any deal to protect the young undocumented immigrants known as Dreamers. The Dreamers are comprised of roughly 800,000 young immigrants brought here illegally as children. The demands represented terms that hard-line conservatives have been pursuing for decades.

Administration officials say that the changes requested by the president are needed to protect American workers from unfair competition and reduce the flow of illegal immigrants into the country. Mr. Trump said in a letter to lawmakers that his requirements would address “dangerous loopholes, outdated laws and easily exploited vulnerabilities” in the immigration system. Officials said the demands were developed by a half-dozen agencies and departments.

According to officials, the demands include the construction of a wall across the southern border, tougher laws for those seeking asylum, the hiring of 10,000 immigration agents, and denial of federal grants to “sanctuary cities.” Stripping away the rights of illegal immigrants to claim asylum, or make some other case for staying in the United States, would allow federal officials to more quickly deport them.

The demands also include a provision that companies use the E-Verify program to keep illegal immigrants from getting jobs and the elimination of loopholes for children fleeing violence in Central America. This year, nearly 39,000 children have been apprehended at the border without their parents. The plan also calls for an end to people bringing their extended family into the United States. The president would limit residents to bringing only spouses and children.

The demands may derail the new bipartisan push to reach a legislative solution to the issue. The president had pledged to work across the aisle to protect the Dreamers with legislation. Senator Chuck Schumer of New York and Representative Nancy Pelosi of California, the Democratic leaders in the Senate and the House, said after a White House dinner last month that they had reached a deal with Mr. Trump to protect Dreamers.

The president abruptly ended the Deferred Action for Childhood Arrivals, or DACA, last month, deferring implementation for six months so Congress could come up with legislation to replace it. By March, thousands of Dreamers will begin losing permission to work and protection from deportation in the absence of new legislation protecting them.

Immigration activists have long opposed many of the proposals being demanded by the White House. Democratic leaders are likely to refuse a deal that includes the president’s terms. Mr. Schumer and Ms. Pelosi declared in a joint statement, “The administration can’t be serious about compromise or helping the Dreamers if they begin with a list that is anathema to the Dreamers, to the immigrant community and to the vast majority of Americans.”