washington trump administration top trade officials hope keep north american free trade agreement trilateral deal negotiations canada mexico revamp 23-year-old pact senators say tuesday several members senate finance committee say commerce secretary wilbur ross new u.s. trade representative robert lighthizer tell close door meet would prefer current three-nation format leave open possibility parallel bilateral agreements canada mexico preference trilateral democratic senator debbie stabenow tell reporters meet republican senator charles grassley iowa say meet sound trilateral deal likely unless problems approach trilaterally get anyplace suppose bilaterally grassley say ross float idea two bilateral trade deal canada mexico decline confirm administration preference trilateral approach right trilateral deal shall see come future important thing get substance ross tell reporters leave meet add talk would long complicate meet one several capitol hill week involve lighthizer swear u.s. trade representative monday require trump administration trigger start nafta negotiate process 90-day consultation period farm state senators say also warn ross lighthizer take action would damage agricultural export canada mexico make pretty clear priority want see ag hurt say senator john thune south dakota republican nafta large good agriculture see disruptions ag marketplace today uncertainty head senator ron wyden oregon finance committee top democrat say ross lighthizer assure would push drop nafta dispute-resolution mechanism trump complain mechanism bias unite state trump trade officials prefer tri-lateral nafta deal u.s. senators