Most airlines in the Mid East when given descent, "Descend now, FLxxx with xxxxfpm give the read back perfectly then....
2 minutes later still at the cruise, confirm that was at our discretion?
Seriously you european pilots, this happens all the time here
Could we maintain for another x Miles? would be the easiest way to ask if its just for efficiency, we'll usually know what you are getting at.
If its due to wx, add that to the question and you'll almost never get knocked back.