The administration of American President Donald Trump is considering new restrictions on Chinese students entering the U.S.

　　U.S. officials say increased concerns over spying and the loss of new technologies are among the reasons.

　　In June, the U.S. State Department shortened the length of stay for visas given to Chinese graduate students studying in several fields. The fields include flight, robotics and some kinds of manufacturing. Visas were shortened from five years to one.

　　At the time, the officials said the goal was to limit the risk of spying and of the loss of intellectual property that is important to national security.

　　Now, the Trump administration is considering whether to carry out additional investigations of Chinese students attending U.S. schools.

　　Reuters news agency reported that officials want to examine student phone calls. They also are considering looking at students' personal accounts on Chinese and U.S. social media sites.

　　Security officials are expected to train education officials on how to uncover spying, as they now do for people in the government, a U.S. official said.

　　The U.S. State Department said, "The department helps to ensure that those who receive U.S. visas are eligible and pose no risk to national interests."

　　The Chinese government has said that the U.S. overstates the problem for political reasons.

　　China's ambassador to the U.S., Cui Tiankai, said "Why should anybody accuse them as spies?"

　　However, a closer watch on Chinese students would be part of a bigger effort to deal with the loss of new technologies. U.S. officials are concerned about unlawful methods China may use to make quick technological gains.

　　China wants to be among the leaders in technologies such as electric cars and robots, as called for in its "Made in China 2025" plan.

　　In addition, China and the U.S. are currently in a trade war. The U.S. has placed import taxes on Chinese steel and aluminum and billions of dollars in other goods. China has answered with its own import taxes on U.S. products.

　　American officials told Reuters that any policy changes would need to balance security with the needs of schools and development.

　　Universities and colleges need talented students in important technological fields. They also depend financially on students' tuition and the economic activity they support. About 360,000 Chinese students who are attending U.S. schools bring in an estimated $14 billion to local economies.

　　Research schools such as Harvard, Yale and Princeton universities campaigned against efforts to change visa policies this summer and are concerned about other possible restrictions.

　　U.S. officials say there are reasons for a closer look at Chinese students. They note recently reported spying cases against former students from Louisiana State University, Duke University and the Illinois Institute of Technology in Chicago.

　　Christopher Wray is the director of the Federal Bureau of Investigation. In February, he told a Senate committee that he is concerned about "non-traditional collectors" seeking intelligence.

　　Opposition to a ban

　　Media reports say White House adviser Stephen Miller has proposed a ban on student visas for Chinese nationals.

　　However, Reuters reports that new measures will not include a ban. Terry Branstad, a former governor of Iowa and U.S. ambassador to China has told officials that a ban would hurt universities across America.

　　Terry Hartle is a vice president at the American Council on Education in Washington, D.C. He said Chinese students are at risk of becoming, in his words, "pawns" in the U.S.-China dispute.

　　I'm Mario Ritter Jr.

　　Reuters reported this story. Mario Ritter Jr. adapted it for VOA Learning English. Caty Weaver was the editor.

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