washington u.s. commerce secretary wilbur ross say thursday unite state seek add five-year sunset provision north american free trade agreement provide regular systematic re-examination trade pact ross tell forum host politico u.s. trade representative robert lighthizer agree need sunset provision mean nafta would automatically end five years unless renew would put forward nafta modernization talk unclear whether canada mexico would back u.s. canadian mexican negotiators set reconvene third round talk ottawa sept. 23-27. ross say sunset provision need forecast u.s. export job growth nafta take effect 1994 wildly optimistic fail live expectations canadian mexican ambassadors washington push back idea say provision would add uncertainty nafta agreement affect long-term plan businesses believer sunset clauses things set temporary say canada ambassador david macnaughton discussion really suspect mexico canada push back secretary lot americans too mexico ambassador unite state gerónimo gutiérrez fernández say provision would detrimental consequences business sector unite state mexico canada let look think detail certainty key word say gutierrez ross say termination clause currently nafta allow country exit six-month notice period never trigger kind thing probably be ross trump talk quit nafta renegotiate reduce u.s. trade deficits mexico canada five-year thing real thing would force systematic re-examination ross say systematic re-examination little experience period forum try fix things work way think would u.s. want nafta five-year sunset provision commerce 's ross