Thank you for the quick response. I suspect you're probably right, since most UK Blu-ray's with Portuguese are European Portuguese, but there are exceptions sometimes. Are you able to confirm from listening that it is European, or are you making an educated guess? Thanks!
I've seen confirmation from two people (one from Portugal, one from Brazil) that it is indeed European Portuguese on the UK disc.
For anybody looking for a version with Brazilian Portuguese, the Hong Kong version is supposed to have PT-BR audio and subtitles, and is Region A so it will work in US players. It is currently $36 with free shipping on play-asia.com. The Korean version should also have PT-BR.