Now, from reading your comments, I'm going to assume you are in good faith, and you simply can't see what consequences they can face.
Although we can't know for sure such things without being an expert in middle-east politics, one can understand that if two groups of people have been at odds with each others for a long time, suddenly doing business with the opposite party is going to have political consequences.
E.G: assuming you are American. If you are a republican group, you can get financed by a left-leaning institution, but this will have political consequences.
I don't think that's a short way of saying the same thing though, for the kind of consequences you mean at least. Imagine if I were a vegan for ethical reasons. It'd be fine for me to say "I don't eat meat", but a lie to say "I can't eat meat", since I'd be perfectly capable of doing so, and be fine if I did, and just not want to anyway. Contrast this with if I had alpha-gal syndrome and someone me offered me a steak. In that case, I could truthfully say "I can't eat that".
But that's not how most human communication work. When people say "I cannot come tomorrow", they usually don't mean they can't. If you gave them one billion dollars to come, chances are they would.
This is a fairly common convention, and most people in the English language are using this approximation and assumption.
You can chose to ignore it of course.
I consider I've done my part in this conversation, and wish you a nice day.
It's not even how it can work. See the Malicious Genie problem for a memorable demonstration of the fundamental problem. Chasing "precision" beyond what's necessary tends to harm communication, not aid it. Norms and context are super-important.
Using the definition that you gave, yes they would be able to trade, because many of those bad consequences of trading have gone away.
It would be a terrible idea, with drastic consequences. But they absolutely can.
If the person said: "eat this steak and I'll give you a billion dollars or don't, and I'll kill everyone on this planet in the most painful way imaginable, including you", I doubt your response would be "I can't eat that".
