#to hang

Hereditary issue

My mother made a will a long time ago, according to which she bequeathed everything to me (a private house and a plot of land). I have an older brother who is a Canadian citizen. My mother had a verbal agreement with him that he does not need our Ukrainian property, and my brother is not mentioned in the will. At the time of my mother's death, my brother turned 67 years old, that is, he received the right to a mandatory inheritance. Question: Should my brother expel from Canada a written refusal of mandatory fate, or is it enough for him to simply not make himself known for half a year? Does it matter that he has not been a citizen of Ukraine for a long time?