::::Looks like Kudpung forgot to sign. Sorry, I hadn't noticed.  
 :::: is the general pronunciation in the sense that, while both  and  are found, both in Britain and abroad, the latter can be predicted from the former, but not vice versa. For the same reason, the general pronunciation of the New in New Mexico is /nju:/, even though locals (and I) do not have a /j/. I presume that Kudpung is correct when he says that the local pronunciation is . Whether the RP pronunciation is  or  would depend on whether the British Library is correct when it says that RP has linking ar, or Kudpung is correct when he says that it does not. From what I've seen, it seems that RP only has linking ar in formal and old-fashioned registers. Thus a transcription of the national pronunciation would depend on how formal we wish Wikipedia to be. But personally I don't see the need for national standards, whether English, Welsh, Usonian, or Australian. In most cases, at least, they don't add anything if we already have a local and generic pronunciation. I'm sure there are exceptions, but this doesn't seem to be one of them.