:Linking r:

A connected speech feature of lower rhoticity accents of English. In such accents an /r/ corresponding to the spelling is generally employed when the next sound is a vowel. This means that words like far and more are pronounced without /r/, when occurring before a pause or before a word which begins with a consonant. However, in phrases like far away and more ice the /r/ is employed. Llinking r is optional, but very frequently used across a word boundary , as in the examples above. Word-internally, as in soaring, warring the absence of linking r is unusual.

See also intrusive r.