All perfect praise be to Allaah, the Lord of the worlds. I testify that there is none worthy of worship except Allaah and that Muhammad, sallallaahu ‘alayhi wa sallam, is His slave and Messenger.
Once Zakah becomes due on you, it is impermissible for you to delay paying it, except for a legitimate excuse, such as the absence of the money, or in expectation to give it to a righteous poor person or a relative, provided that the waiting period is short.
Consequently, you should pay Zakah to those entitled to it once it becomes due upon you and it is impermissible for you to give loans from it or delay to pay it in any way. You may loan your friend from your property rather than from the money of Zakah. If he is among those entitled to Zakah, then you may give him from it rather than loan him.
Allaah Knows best.