Wayne Couzens, 48, made the guilty plea at the Old Bailey - the central criminal court - in London on Tuesday, an Old Bailey clerk told CNN.
Asked how he pleaded to the charge of rape, Couzens again replied: "Guilty, sir".
Couzens, who appeared via videolink from Belmarsh prison, has not entered a plea to murder and is being medically assessed.
A serving Metropolitan Police officer has suddenly entered pleas of guilty to kidnapping and raping Sarah Everard and has "accepted responsibility" for her death.
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The shooting took place just a week after 23 people were shot, including two killed at a concert in the same area. Authorities found at least one gun in the vehicle , but its exact connection to the shooting was unclear.
Marketing executive Ms Everard, 33, went missing as she walked home from a friend's house in Clapham, south London, on March 3.
Her body was found hidden in an area of woodland in Ashford, Kent, on March 10.
The phrase "she was just walking home" began to trend on social media after her disappearance, with masses of women sharing their horror and outrage at what had happened, as well as the precautionary measures they constantly take in order to feel safe.
Her body was discovered a week later in woods some 80 kilometres (50 miles) away in Kent, southeast England.
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Les ressortissants de quelques autres pays, comme la Chine ou le Japon, sont, eux aussi, exemptés de toute restriction. A partir de lundi, les frontières de ce pays touristique s'ouvrent à toutes les personnes vaccinées du monde entier.
The court heard that responsibility for the killing was admitted but medical reports were awaited.
"It is hoped that the issue in relation to count three can be resolved at the plea and trial preparation hearing on July 9 - by which time it is the hope of the court that the psychiatric and psychological reports commission by the defence will have been completed and will be available".
A post-mortem concluded earlier this month that she had died as a result of compression of the neck. There is no suggestion anyone else was involved.
Miss Everard's death prompted a national debate around female safety and has increased demands for more to be done to tackle violence against women.
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Vice President Harris had what she called "robust" talks with Guatemalan President Alejandro Giammattei . Harris discussed sharing COVID-19 vaccines with Guatemala during the meeting, she said.
A vigil in memory of Ms Everard ended in ugly scenes when the police moved in to break up a large gathering that was in breach of lockdown restrictions.