China has imposed travel restrictions on Tuesday as new exit and entry rules took effect, barring citizens deemed as potential threat to national technology security from leaving the country.

Chinese, who are generally free to travel, unlike during the height of the Cold War, when few were enabled to venture overseas, but the government has long kept close watch of the travel plans of those it considers to pose a security threat.

China unveiled the new rules in July. Under the new laws, violations of export controls or technology import and export rules are addressed in a strict manner as they may endanger industrial or technological security.

As per the new rule, an exit ban ranging from six months to three years on citizens who return to China after committing illegal crimes or criminal acts abroad that harm national security or interests has been levied.

Foreign nationals may also be denied entry for one to five years for false statements made in visa applications.

Curbs in personal foreign travel have long applied to senior government officials and state executives with access to confidential information.

According to a report, Chinese civil servants and employees of state-linked enterprises since 2023 are facing tighter limits on private travel abroad and scrutiny of foreign connections as the country waged a campaign against foreign influence.

Besides foreign governments, there are also reported cases of citizens being denied permission to leave the country, often due to security-related investigations.

The latest rules have prompted Taiwan, which Beijing views as its own territory, to warn its people to take extra care on visits to China, which considers people from Taiwan to be Chinese citizens.

The new rule legalizes previously unfolded border control practices and boosts the discretionary authority of enforcement agencies, said deputy head of Taiwan’s China policy-making Mainland Affairs Council.

On Monday, he highlighted the new language on export control and technology import-export management as a particular concern and said it could serve as grounds for restricting exit, especially for Taiwanese who work in the tech sector.