connective N1 rare writtenliterary
〜は言うに及ばず — needless to say ~
〜は言うに及ばず ・ 〜はいうにおよばず
Builds on 〜は言うまでもなく
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See 〜は言うに及ばず in real sentences
Jengo shows 〜は言うに及ばず the way you actually meet it: inside real Japanese sentences, so it sticks instead of staying an abstract rule.
Study it in JengoSources Compiled with reference to A Dictionary of Advanced Japanese Grammar, A Dictionary of Intermediate Japanese Grammar. Editorial confidence: medium.