A U.S. diplomat was fired on Wednesday after the State Department found out that he was in a romantic relationship with a Chinese woman accused of having ties to the Chinese Communist Party, Fox News confirmed. 

President Donald Trump reviewed the case and approved the diplomat’s firing, Tommy Pigott, a State Department Principal Deputy Spokesperson, said in a statement. He said the diplomat “admitted concealing a romantic relationship with a Chinese national with known ties to the Chinese Communist Party.”

“Under Secretary Rubio’s leadership, we will maintain a zero-tolerance policy for any employee who is caught undermining our country’s national security,” Pigott added.

In Beijing, a Chinese government spokesperson declined to comment on what he described as a domestic U.S. issue. 

“But I would like to stress that we oppose drawing lines based on ideological difference and maliciously smearing China,” the Foreign Ministry’s Guo Jiakun said at a daily briefing, according to The Associated Press. 

In January, as the Biden administration came to a close, the U.S. government moved to ban American government personnel in China from having sexual or romantic relationships with Chinese citizens, the AP reported. This ban also applied to contractors with security clearances and relatives of American government personnel.

The Trump administration intensified its scrutiny of Chinese nationals studying at U.S. universities in May following several instances of students allegedly engaging in surreptitious activity, including espionage.

Secretary of State Marco Rubio said at the time that the State Department and the Department of Homeland Security planned to “aggressively revoke” student visas of Chinese nationals, “including those with connections to the Chinese Communist Party.”

Donald Trump says 600,000 Chinese students could be allowed into the U.S. to study at its colleges pending a potential trade agreement with China. (Fox News)

However, the president’s push to open the door to 600,000 Chinese students in late August sparked backlash, with conservatives wondering why the administration was making the move. Trump said that he believed it was important to have Chinese students in the U.S., but that the country needed to be cautious and keep track of who was coming.

Fox News Digital reached out to Chinese government representatives for comment.

Fox News’ Nicholas Kalman, Fox News Digital’s Digital’s Ashley Oliver and Cameron Arcand and The Associated Press contributed to this report.