US President Donald Trump has signed executive orders targeting TikTok and WeChat, two of China's biggest apps, BBC News reported.

Under the orders, US firms must stop doing business with the companies within 45 days.

The executive orders against TikTok—owned by Chinese firm ByteDance—and WeChat—owned by the Tencent conglomerate—is the latest measure in an increasingly broad Trump administration campaign against China.

In both executive orders, Trump says he has found "additional steps must be taken to deal with the national emergency with respect to the information and communications technology and services supply chain".

He adds: "The spread in the United States of mobile applications developed and owned by companies in the People's Republic of China (China) continues to threaten the national security, foreign policy, and economy of the United States."

The text of Trump's order says TikTok's data collection could allow China to track US government employees and gather personal information for blackmail, or to carry out corporate espionage.

He notes that reports indicate TikTok censors content deemed politically sensitive.