A Chinese student on Wednesday pleaded not guilty to carrying a knife near Buckingham Palace, the official residence of Queen Elizabeth II.
Zhang Hang, 25, denied a charge of possessing an offensive weapon in a public place, during a court hearing in London.
Zhang was found close to the main gate of Buckingham Palace in London on August 12.
He has been detained under the Mental Health Act and is receiving medical treatment.
He is due to stand trial from December 8.
Buckingham Palace is the official residence of Queen Elizabeth II.
