Nus Poland News Today

World are gathered to finalize details of the paris accord rule book and working to establish the guidelines that countries will eventually use when the agreement takes effect in 2020. our senior international correspondent nick payton walsh is joining nus poland. flick, what issues still have to be resolved here? because i understand part of the problem is the trump administration is causing a little bit of a delay by rejecting some of the science? >> absolutely. you joined me at a very key tim...