Thanks for the context! Assuming that this is about the second stage, when the initial rush is over, this could work,or:

Tomorrow or the next day


OR, if "demain" doesn't refer specifically to the day after today (!), then it could be

"The next day or the day after that, it makes no difference"

or "... or the following day,..."

Agree with Emma and writeaway that it would be best to go back to the Arabic to find out what the expression means and translate it directly into English; but in case you aren't able to, or are pressed for time, here's my tentative suggestion.

I think...it might mean that one can act on the present, based on immediate circumstances, but one can't foresee or control future events.
So, in an aid context, it might refer to how most agencies are well geared to handle emergencies and crises, but are generally unable to prevent or deal with long-term institutional or endemic problems; that contrast might be a source of frustration for them, since the sudden crises are often the result of entrenched problems.

I admit it's a thumbsuck :-) but maybe it will help a little.

It could be this... depending on the context of course.

in the sense of "as long as it takes" as you suggested