There is a proposal, backed by the U.S., to cap the price of oil and gas purchased from Russia. Janet Yellen, the U.S. Treasury Secretary, is apparently attempting to find international support for this plan. I am skeptical that this proposal will work, but it is not impossible.
The first thing to remember is that even if it does work, the objective is to deny Russia some of the revenues from its energy exports. Even if it worked perfectly, it would not lower world oil and gas prices. Why? Because world oil and gas prices are determined by global supply and demand. Capping the price that Russia can receive for its exports will not affect either supply or demand, unless it causes Russia to export less.
That is not to say that a price cap is a bad idea. There are two ways in which it might work.
The first way recognizes that the West has a degree of market power over Russian exports that must arrive by pipeline. If there is no feasible way for Russia to redirect these exports to other markets, Western countries can exercise that power by collectively refusing to pay more than the cap. If Russia wants any revenue from these exports it must accept the price cap. The oil and gas purchased through this buyer’s cartel can then be resold at market prices. The best way of doing this is for the oil and gas to be auctioned off by the buyer’s cartel with the difference between the price cap and the market price being shared by the participants in the buyer’s cartel.
The second way that the price cap might work, that is often mentioned in the press, is for the West to use its control over finance, shipping and insurance markets to coerce Russia to sell its oil and gas exports at the price cap. The problem with this mechanism is that it would be difficult to prevent purchasers from separately compensating Russia for the sale. If China or India, for example, receive the discounted oil and gas they can have a side deal to pay Russia the difference between the price cap and the market price or some portion of it. It is not at all clear to me how we intend to prevent these side deals. It is also not clear to me why Russia would sell its exports to anyone unwilling to provide the side payment.
My feeling is that the first of these two plans is plausible and worth trying. The second proposal strikes me as very difficult to execute effectively. It would leak faster than a ruptured tanker.