Ah, the wonders of open forums! As crj705 pointed out, he asked a simple, direct question, and waited a goodly while until WX-T answered it.
There are semantic subtleties in the ICAO suggested phraseology which might be missed without careful reading.
Let's assume a non-radar environment. You, as pilot, require a deviation but you can only request clearance for it, for clearance is not yours to determine or assure. The response may be "unable", if someone has already booked the airspace. Which is presumably why ICAO suggest you assert priority handling with a PAN declaration.
PBL