The term "UNCLASSIFIED" or "NOT PROTECTIVELY MARKED" may be used in UK Government documents to indicate positively that a protective marking is not needed.
ðə tˈɜːm "ʌŋklˈæsᵻfˌaɪd" ɔːɹ "nˈɑːt pɹətˈɛktɪvli mˈɑːɹkt" mˈeɪ biː jˈuːzd ɪn jˌuːkˈeɪ ɡˈʌvɚnmənt dˈɑːkjuːmənts tʊ ˈɪndᵻkˌeɪt pˈɑːzᵻtˌɪvli ðˌæɾə pɹətˈɛktɪv mˈɑːɹkɪŋ ɪz nˌɑːt nˈiːdᵻd.