A 21-year-old man has been arrested after climbing over a gate in broad daylight at Buckingham Palace.

Scotland Yard said they were alerted to the man scaling the royal residence's south gate shortly before 1.45pm.

"As he dropped to the ground he was met by officers and arrested for trespassing on (a) designated site," police said in a statement.

The man, who was not carrying an offensive weapon, was taken into custody and will undergo a mental health assessment.

Police confirmed inquiries are continuing.