Midrash for Sotah 81:6

והתניא מדלגין בתורה בענין אחד ובנביא בשני עניינין וכאן וכאן בכדי שלא יפסוק התורגמן

the other teaching to where there are two themes. Thus it has been taught: We may skip [a passage] in the Torah where there is one theme and in the Prophets where there are two themes, but in either case only when it is not sufficiently long to interrupt the translator. We may not, however, skip from one Prophetical Book to another; but with a book of the Minor Prophets<span class="x" onmousemove="('comment',' These are regarded as one Book. ');">⁵</span>

Sifrei Devarim