Secretary of State Marco Rubio announced on Wednesday evening that the Trump administration would work to “aggressively revoke” visas of Chinese students, including those with ties to the Chinese Communist Party or studying in “critical fields.”

He added that the State Department was revising visa criteria to “enhance scrutiny” of all future applications from China, including Hong Kong.

The move is certain to send ripples of anxiety across university campuses in the United States and spur recriminations in China. China is the country of origin for the second-largest group of international students in the United States, and many universities rely on Chinese and other international students paying full tuition for a substantial part of their annual revenue.

American universities have also benefited over many decades by drawing some of the most talented students from China and other countries. Chinese students and researchers are represented in large numbers in university science laboratories.

Although Mr. Rubio’s written statement did not define “critical fields,” the phrase most likely refers to research in the physical sciences. In recent years, American officials have expressed concerns about the Chinese government recruiting U.S.-trained scientists, though there is no evidence of such scientists working for China in large numbers.

It is unclear how quickly the State Department and the Department of Homeland Security will cancel the visas and revoke the status of affected Chinese students now in the United States. The Immigration and Customs Enforcement agency, or I.C.E., has aggressively moved to detain some students whose visas or residency status have been canceled by Mr. Rubio. That has led to lawsuits against the Trump administration.