Although I doubt if China would do anything here to help Pakistan, if worst comes to worst, we can put tariffs on China as well. Our balance of trade with them puts us in the stronger position in this regard.
That we even let our own share go to Pakiland is absurd.
I am for scrapping the entire treaty itself, but that our previous governments couldn't even use the water we ourselves own and instead let it flow to an enemy country is idiotic.