 These ships would have been much larger and more expensive than earlier vessels and President Warren G. Harding called a conference at Washington, D. C. in late 1921 to forestall a very expensive arms race.The attendees at the conference agreed to limit capital ship construction for the next decade and scrapped large numbers of existing ships as well as many ships still under construction.Japan suspended the "Number 13" class while the conference was in progress before any ship was laid down and formally cancelled them on 19 November 1923.