As a romanian i have to disagree with you... The entire population of Romania is about 22.000.000 and is member of EU from 2007, so they won't invade you next year, they're here already ...
I can asure you, they will perfectly understand why you don't want to employ any of them, as most of them, as myself, studied english from 2nd grade in primary school all the way to college and uni... Funny thing is i've got a operations manager job over two english candidates... and i'm not even speaking english...