RE: For Those Who Work In Banking
They need written authority mate, (specimin of signature), and they won't close without it. As mentioned before, keep it open with nothing in and you'll forget about it before to long and the bank will "deactivate" it. When/if you return simply walk into a branch with photo ID and "reactivate".
If you really want it closed then ask to raise a concern with the bank and they may be prepared to send you a letter on international signed for service how ever some banks charge you for that service, some don't.
I'm here to attain not maintain