Command to find out the version number of a .pkg file

Does anyone know how to retrieve the version number of a .pkg file which isn't installed yet? I'd like to use something like **pkgutil --pkg-info**, but that only works for installed packages. I've also tried **installer -pkginfo -verbose**, but that doesn't show the version number. Is there a built-in command to do this, or alternatively, could someone suggest a one-liner please? Thanks.