The phrase “there is no hurry” means that you are telling the other person
- the work is not urgent,
- they do not need to hurry, and
- they can “take their time”. (definition)
You can also say “there is no rush”, “take your time”, or “don’t rush.”
You can say (informally), “No rush.” (This is a sentence fragment.)
Using “no rush“ or “no hurry” in this way is an idiom.
You can’t say the opposite:
There is hurry.
There is rush.
Instead, you would say:
This is urgent.
Time is of the essence. (another idiom)
This is important to me.
I need this done by 5 p.m.