Some phonemic mergers are characteristic of non-rhotic accents. These usually include one item that historically contained an R (lost in the non-rhotic accent), and one that never did so.
This merger is present in non-rhotic accents which have undergone the weak vowel merger. Such accents include Australian, New Zealand, most South African speech, and some non-rhotic English speech (e.g. Norfolk, Sheffield). The third edition of Longman Pronunciation Dictionary li…