Just a month before the Group of Seven rich countries plan to cap the price of Russian oil, officials are racing to finalize details, leaving traders, shippers and insurers with questions about the price level and how it will work.

Officials from the United States and its G7 allies plan to cap prices of seaborne oil shipments effective Dec. 5, with a second cap on oil products kicking in Feb. 5.

The unprecedented price cap aims to block Russia from profiting from high oil prices after its Feb. 24 invasion of Ukraine while ensuring that most of Russia's oil continues flowing to global energy markets.