9 7 1 - 1 9 7 2 ), ▁Le ader ▁of ▁the ▁Liberal ▁Party ▁( 1 9 7 1 - 1 9 7 2 ), ▁Deput y ▁Le ader ▁of ▁the ▁Liberal ▁Party ▁( 1 9 6 6 - 1 9 7 1 ), ▁Minister ▁for ▁Foreign ▁Affairs ▁in ▁the ▁G orton ▁Government , ▁Tre as urer ▁in ▁the ▁Hol t ▁Government ▁and ▁G orton ▁Government , ▁Minister ▁for ▁Labour ▁and ▁National ▁Service ▁in ▁the ▁M enz ies ▁Government , ▁Minister ▁for ▁Primary ▁Indust ry ▁in ▁the ▁M enz ies ▁Government , ▁Minister ▁for ▁Social ▁Services ▁in ▁the ▁M enz ies ▁Government , ▁Minister ▁for ▁the ▁Navy ▁& ▁Air ▁Force ▁in ▁the ▁M enz ies ▁Government ▁and ▁former ▁Vice ▁President ▁of ▁the ▁Executive ▁Council ▁ ▁Sir ▁Robert ▁M enz ies , ▁K T , ▁A K , ▁CH , ▁Q C , ▁F AA , ▁F RS , ▁longest - ser ving ▁Prime ▁Minister ▁of ▁Australia ▁( 1 9 3 9 - 1 9 4 1 ▁& ▁ 1 9 4 9 - 1 9 6 6 ), ▁Le ader ▁of ▁the ▁O pp osition ▁( 1 9 4 3 - 1 9 4 9 ), ▁inaug ural ▁Le ader ▁of ▁the ▁Liberal ▁Party ▁( 1 9 4 5 - 1 9 6 6 ), ▁Le ader ▁of ▁the ▁United ▁Australia ▁Party ▁( 1 9 3 9 - 1 9 4 1 ▁& ▁ 1 9 4 3 - 1 9 4 5 ), ▁Deput y ▁Le ader ▁of ▁the ▁United ▁Australia