needs must
Said when something is necessary but undesirable, unpleasant, or unfavorable. I didn't want to drive all the way across town again to collect the bed, but needs must. I already had plans for this evening, but if needs must I can take you to the airport.
needs must
sometimes you are forced to take a course of action that you would have preferred to avoid. This is a shortened form of the proverb needs must when the Devil drives , which is first found in a work by the medieval author John Lydgate .
needs ˈmust (when the devil drives)
(saying) in particular situations it is necessary for you to do something you do not like or enjoy: Of course I’d rather go to the beach than sit here studying for my exams, but needs must I suppose.