Britain will review its security following the incursion of a suspected Chinese surveillance balloon into U.S. airspace earlier this month, Defence Secretary Ben Wallace said.
Prime Minister Rishi Sunak said the government would do "whatever it takes to keep the country safe".
The United States shot down the balloon, which it said was being used to spy on it, and three further flying objects have since been downed by security forces over North America.
Beijing has claimed it was a weather balloon that had blown off course and accused the United States of overreacting.
"The UK and her allies will review what these airspace intrusions mean for our security. This development is another sign of how the global threat picture is changing for the worse," Wallace told the Telegraph.
The newspaper reported that the security review would be used to help decide whether changes need to be made to the surveillance of British airspace.
Asked about the UK review during a regular briefing in Beijing, Chinese foreign ministry spokesman Wang Wenbin said: "We have already stated our position on the incident in question. All parties should look at it objectively and stop playing up the issue."
Sunak declined to comment on national security when asked by reporters whether he was aware of any spy balloons being spotted over Britain, but said Britain's capabilities included its Quick Reaction Alert force whose Typhoon jets police UK airspace.
The spectacle of the Chinese balloon drifting over the United States caused political outrage in Washington and brought into sharp focus the challenge posed by China to the United States and its allies.
Asked on Sky News on Monday if it was possible Chinese spy balloons had already been used over Britain, junior transport minister Richard Holden said: "It is possible."
"The government is concerned about what's going on," he said. "China is a hostile state and we need to be aware of that and the way it acts and behaves."
(Reporting by Kylie MacLellan in London, additional reporting by Martin Quin Pollard in Beijing; Editing by Emelia Sithole-Matarise, Mike Harrison and Shounak Dasgupta)
