But she said the greatest challenge was posed by China.
China poses a genuine and increasing cyber risk to the United Kingdom, the head of British spy agency GCHQ said on Tuesday, adding that while Russia and Iran represented an immediate threat, Beijing was an epoch-defining challenge.
"As the prime minister said yesterday, the next few years will be some of the most dangerous and transformational," Anne Keast-Butler told a security conference in Birmingham, central England.
In her first major public speech since being appointed director of the intelligence communications agency last year, Keast-Butler said the threat from Russia was acute and globally pervasive, while Iran remained aggressive in cyberspace.
But she said the greatest challenge was posed by China.
"In cyberspace, we believe that the PRC's (People's Republic of China) irresponsible actions weaken the security of the internet for all," she said.
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