There is no such thing as the “right of return” as an internationally recognized legal right.
When the term is used, it refers to the alleged right of Arabs who fled Israel during the course of the war in 1947-48 to come back to Israel.
UNRWA, the UN agency charged with care of the Palestinian Arab refugees, would have you believe that there is a right in this regard. There is a reference in its mandate specifically to United Nations General Assembly Resolution 194, paragraph 11, which says, in its lead sentence, “the refugees wishing to return to their homes and live at peace with their neighbors should be permitted to do so at the earliest practicable date…”
However, resolutions of the General Assembly of the UN are only recommendations — they have no status in international law.
What is more, while the resolution states as a condition of return the desire of the refugees to live at peace with their neighbors, it is unarguably clear that the intent of the refugees with regard to Israel is not peaceful.
All other refugees in the world other than the Palestinian Arab refugees are the responsibility of the UN High Commission for Refugees, which maintains a policy of settling refugees elsewhere when repatriation is not possible. No principle has been established that requires repatriation.