All perfect praise be to Allah, The Lord of the Worlds. I testify that there is none worthy of worship except Allah, and that Muhammad is His slave and Messenger.
Merely setting aside an amount with the intention of spending it without declaring that it is for charity does not place this money outside one's ownership; rather, it is still part of his holdings.
Therefore, the questioner may spend that money on his poor, needy relatives and others. The evidence for this decision is the saying of the Prophet that “Who observes fast voluntarily is just like the one who sets apart Sadaqah out of his wealth. He may spend it if he likes, or he may retain it if he so wishes”. [An-Nassaa’i and Muslim]
Allah knows best.