China has accused the United States of "bullying" and threatened to take "necessary" countermeasures after Washington banned downloads of the Chinese video-sharing app, TikTok, and effectively blocked the use of the messaging super-app, WeChat.
Separately, Beijing also launched on Saturday a mechanism enabling it to restrict foreign entities that it deems a threat to its sovereignty and security, in a development seen as retaliation to US penalties against other Chinese companies such as telecom giant Huawei.
The latest Chinese moves come as tensions with the United States escalate on a range of issues from trade and human rights to the battle for tech supremacy.
In a statement on Saturday, the Chinese Ministry of Commerce condemned Washington's Friday decision to ban TikTok and WeChat from US app stores, saying: "China urges the US to abandon bullying, cease its wrongful actions and earnestly maintain fair and transparent international rules and order."
It then warned: "If the US insists on going its own way, China will take necessary measures to resolutely safeguard the legitimate rights and interests of Chinese companies."
The US Department of Commerce announced the bans in response to a pair of executive orders signed in August by US President Donald Trump, in which he said the two Chinese-owned apps presented a threat to the country's national security.
China and the companies, however, have denied US user data is collected for spying.
Under Friday's order, the Tencent-owned WeChat app would lose functionality in the US from Sunday onwards, while TikTok users will be banned from installing updates but could keep accessing the service through November 12
WeChat developer Tencent Holdings' called the order "unfortunate" and said it "will continue to discuss with the government and other stakeholders in the US ways to achieve a long-term solution".
The owners of TikTok, which has 100 million users in the US, said it will challenge "the unjust executive order".