Again, we haven't made a decision on whether or not this is a good idea, but in the context of different countries taking on the idea, then it's much better to do things multilaterally so that we're all working under the same rules and preventing disputes. If that were the case, the WTO is the best place.
Multilateral solutions, such as the G7, are better than nothing, but not as good as the WTO, for different reasons. One is that the WTO has a set of rules that are easier to add on to. It's a legal body. The other one is that it's the whole world, essentially. We trade with people who aren't part of the G7, like China and India. The WTO is where everybody we would trade with is.