WASHINGTON, United States (AFP) — The US said Monday that its travel warning for China, which it relaxed last week after three American prisoners were freed, could move back up if Beijing again arrests its citizens.

US President Joe Biden’s administration last week announced the release of the last American citizens considered by Washington to be wrongfully detained by Beijing.

In turn, the US freed three unidentified Chinese nationals and loosened its travel advice — a hard-fought goal by Beijing as it seeks to draw back foreign businesspeople.

The US State Department as of last week classifies China as level two — “exercise increased caution” — and not level three, which tells Americans to reconsider whether to travel to China.

“They are no longer wrongfully detaining Americans, so they moved back down to level two,” State Department spokesperson Matthew Miller told reporters.

“But it’s true for China, as it is true for any country in the world, that if they are wrongfully detaining our citizens, we will work to get them back, and, of course, it will have an impact on the travel advisories that we issue,” he said.

The Biden administration had repeatedly raised the cases of the three Americans -- Mark Swidan, who was jailed since 2012 on drug allegations, and Kai Li and John Leung, US citizens of Chinese origin accused of espionage. All strongly denied the charges.

“We were determined to get them released before this administration left office, and we have been able to accomplish that,” Miller said.