People are advised to only travel by train if necessary, with just a fifth of services running.
Boris Johnson promises to "listen and learn" but ex-leader Michael Howard calls for him to quit.
The prince also tells Commonwealth leaders it is up to nations whether they remain monarchies.
The government is calling a review of the plans which include a smaller shop, offices and a gym.
The 20-year-old calls the decision to end the constitutional right to abortion a "dark day".