Sorry another question who approaches other depts for funding?

Ok, so is this a PhD that has been advertised as a collaboration between two departments or is this something you are proposing?

For me it was the first, my two supervisors have other students in the same situation and they had enough money together to have one full studentship using funding money.

No it's my ideas but i need funding but it overlaps into another subject area.

But I'm wondering should I aproach toe dept or get my current dept to?