без промедления – English translation

on the word; with the word; quick off the mark; wasted no time (Tanya Gesse); on the spot; in a hurry; right then and there (ART Vancouver); proactively (по контексту Ася Кудрявцева); promptly; swiftly (AMlingua); with urgency (Ремедиос_П); readily (Alexander Matytsin); summarily (Andrey Truhachev); without any delay (reverso.net kee46)

Игорь Миг

on a fast-track basis; expeditiously

amer.

right along (ssn); on an instant's notice (Val_Ships); with no delay (Val_Ships); right off (or "at once" Val_Ships); without missing a beat (Ella forgot the words she had memorized but, without missing a beat, she made up new ones. Val_Ships); at once (You must come here at once. It is an emergency. Val_Ships); in the nick of time (A man walking his dog saw her fall into the river and pulled her out just in the nick of time. Val_Ships); right away (Val_Ships); wasting no time (Val_Ships); in a heartbeat (Just tell me that you need me and I'll come there in a heartbeat. Val_Ships); pronto

econ.

forthwith

idiom.

without any further ado (without further/more ado: (old-fashioned) without delaying; immediately: / "ado" is most often found in the phrases "without much ado," meaning "without much fuss," or "without further ado," meaning "without further delay." (MW): So without further ado, let's get on with tonight's show. Ellisa); off the bat (VLZ_58)

inf.

on the double (Enrica); head-first (Val_Ships); prompt (prompt response Val_Ships)

law

without delay

lit.

without a moment's delay (nouray)

Makarov.

off like a shot; right off the bat

med.

stat (without delay slitely_mad)

mining.

on a short notice