[Lalaith]

I'm as pure RP as they come (I've been officially told by a linguistic-type person...very typical of someone who has been reared in a middle-class English environment with non-native-English speaking parents) and I say fay-vuh.
And fay-v'rt.

But luckily you still get different answers when you ask Brits how "they" pronounce things because different regional accents still exist.
Although they are in danger of being swamped by "telly English", aka "estuary English", or "mockney", which has already taken over most of the regional variations that once existed in southern England - and has been found as far north as Edinburgh.

So I thereby assign the ersatz monstrosity that is estuary English to Mordor.