Let's say, Someone asks me
Are you having dinner right now?
But right now I have an important call to make, so I say
Not right now but I will have it in 4-5 minutes.
Even though I say 4-5 minutes, I don't mean it literally. I want to say that I have got something to do but it would hardly take any time, so even though It is not right now per se but not after very long time also.
What world can I use to say equivalent of 4-5 minutes?