Probably regardless of what it says in your lease (I am almost certain a no subletting clause would be unenforceable, but ianal) he can't prevent you from subletting without letting you out of your lease.
If the condo bylaws prohibit subletting, that would probably be a reasonable and non-arbitrary reason to forbid you to sublet. Otherwise, the landlord can't refuse your request, and if he does, you can go to the Tribunal and get out of your lease.
Here is all you need to know. Unfortunately it doesn't include the letter to write to your landlord so you'll need to figure that out yourself:
http://www.acto.ca/~actoca/assets/fi...tting_0107.pdf
Last edited by gregorio; 10-12-2017 at 07:37 PM.