Pets in rented apartment?

I've looked through my tenancy agreement and it says nothing about requiring permission to have pets. Does this mean I'm ok to get one? I don't fancy asking the letting agent as that gives them the opportunity to say no and I don't think they have a legal right to.. unless I'm mistaken?

We're good people so if the cat in any way damaged the property we'd repair it fully before moving out so there's no issue of courtesy really. (all the furniture is ours anyway so any damage will be our expense!)

The last tenants smoked here, took a couple of months to get rid of the smell and there's nothing in the agreement that says you can't smoke either so I guess that's why they did!

[Drew Carey]

We had specific exclusions for pets. But, we called the landlord and were given permission to keep a tortoise in a cage and a cat. The understanding is that we make good any damage / infestation if / when it occurs.

Its normally a fairly std clause to not have pets unless specific permission is given... Has been on all my previous tenancy's anyway

I rent out a property and it's in my agreements but it's definitely not in the one for the place I'm at now so I can only assume they've opted out and will just carry on.