Anne Keast-Butler, director of GCHQ, pictured during CYBERUK 2024 on May 14, 2024, in Birmingham, England. Matthew Horwood for CYBERUK | Getty Images News | Getty Images Britain and its allies have a “narrowing window” to keep ahead of security risks posed by China, Russia and other adversaries, the U.K.’s top intelligence agent will warn on Wednesday. In a rare public speech, Anne Keast-Butler, the director of GCHQ — the U.K.’s intelligence, cyber and security agency — will say Britain is at a “moment of consequence,” with the country facing increasingly brazen behavior from hostile nations. “China is now a science and tech superpower with sophisticated capabilities across their intelligence, cyber and military agencies,” Keast-Butler is set to say, according to excerpts from the speech released ahead of time by her office. “The ground beneath our feet is shifting,” as AI continues to develop swiftly, she will say, with new technologies creating a “narrowing window for the U.K. and allies to stay ahead.” Earlier this month, two men became the first in history to be found …