The Tokyo Metropolitan Government board of education said Thursday it will punish public school teachers who refuse to raise the Hinomaru flag and sing "Kimigayo" at school ceremonies.
New rules have also been issued detailing exactly how the flag should be positioned and the national anthem sung.
Under the new rules, the board of education will order public schools to raise the Hinomaru "at the front of the stage of assembly halls during a ceremony" and to have the leader of the ceremony urge participants to stand up and sing "Kimigayo" with musical accompaniment.
The old rules had only said the flag should be placed "at the front of assembly halls." The new rules add that it is "inappropriate" for the Hinomaru to be placed on a tripod or anywhere else but the front of the room.
Teachers who do not comply "will be punished" under the new rules, whereas the old rules had stipulated that they "may be punished."
A major teacher union in Tokyo criticized the decision.
The move "will violate people's freedom of thought and conscience, which is guaranteed under the Constitution, by controlling people's minds and education," it said in a statement.