on your hind legs

on (one's) hind legs

Standing upright, especially to deliver a speech. Come on then, stand up on your hind legs and say a few words about this company you've helped create! Forgive me if I seem nervous, but I'm not used to standing on my hind legs in front of a large group of people.
See also: hind, leg, on

on your hind legs

standing up to make a speech. British informal
See also: hind, leg, on
References in classic literature ?
If you haven't room to swing round, rear up a little and come round on your hind legs. That's being bridle-wise."
Extend the neck, chin out, rocking on your hind legs.