Copying Hyper-V VHD file(s) to bitlocked USB drive

Hi everyone,

I've got a Server running Windows Server 2008 R2 SP1with a single VM running Windows 2000 Server and software from the 2000-era

I need to copy the VHD files off the existing hardware and secure/encrypt them on an external USB drive

What is the best way to achieve this?

EG

Bitlock the USB drive then copy the VHD files to this drive which will then be encrypted?

Or is this unsafe if the VHD files can simply be copied off the USB drive and the files will be decrypted?

Thanks