Editing and compressing videos in movie maker

I can happily edit and compress normal videos in MS movie Maker 

However, I have started to use my Samsung 5 phone to shoot video in portrait orientation

When I play them back in VLC, they look great

However, when I try and edit them in MS Movie Maker, it doesn't recognise that they are portrait and fits them into a landscape frame with black margins on each side

Is MS Movie Maker capable of editing video shot in portrait as a portrait video file - and, if so, how?

Or does it ALWAYS convert to landscape?

Thanks, Vincent