“This year’s refugee ceiling reflects the substantial increase in the number of individuals seeking asylum in our country, leading to a massive backlog of outstanding asylum cases and greater public expense,” he added.

Mr. Pompeo said refugees had to be weighed against a backlog of 800,000 asylum seekers who are awaiting a decision by immigration authorities about whether they qualify as in need of protection under United States law and will be granted status to remain.

But he vastly overstated the numbers, while making a linkage between two groups of immigrants that are not the same and are processed differently. As of the end of June, the Department of Homeland Security reported just under 320,000 people who had claimed asylum — meaning they had passed an interview conducted to verify that they met the “credible fear” threshold to be considered — and were awaiting a decision from the department about whether they could stay.

About 730,000 additional immigrants were waiting for their cases to be resolved by immigration courts, according to the Justice Department, including people who had asked for asylum after being apprehended. But that number also included people in deportation or other immigration proceedings. Those are not all “humanitarian protection cases,” as Mr. Pompeo described them; some may never be granted asylum and some will be removed from the United States.

Immigrant and advocates condemned the cuts to the refugee program, calling it a callous decision that would also undermine American national security and foreign policy priorities.

Nazanin Ash, the vice president for policy and advocacy at the International Rescue Committee, accused the Trump administration of piling on after attacks on the American asylum system, failing to protect unaccompanied minors at the border and withdrawing temporary protected status for Haitians, Salvadorans, Hondurans and others.

“This was an opportunity for the administration to show its humanitarian heart,” Ms. Ash said.

“In justifying its policy intention, the administration has pitted those seeking asylum against refugees,” she said. “The administration has the resources it needs to effectively administer both programs, as historic admissions levels prove.”