Unfortunately, Netanyahu is afraid of Lieberman, who is a much tougher man. Lieberman does what he wants, and Netanyahu has to clean up after him. In this case, I suspect that Lieberman did not consult with Netanyahu before he suggested this "exchange" idea to the UN. This is Lieberman's own party platform, not the Israeli governments'. It happens sometimes in negotiations that the Foreign Minister will say to his interlocutor: "Let me raise the following possibility as my own personal idea, which I think my government might accept, and let us continue this discussion for now on this basis." This is fair enough, because the government is not obligated by it. But Lieberman could not say this at the UN. He is just embarrassing the Israeli government and the PM.
Brazilian head of UN peacekeeping force in Haiti dies of heart attack (Reuters)
from the article: Netanyahu: Israel, Palestinians can reach Mideast peace in a year