It is narrated from Usama bin Zaid Al-Laithi, may Allah have mercy on him, that he asked Salim bin Abdullah, may Allah have mercy on him, about Zakat. He said: "You should give it yourself." Usama says: "I said, did not Ibn Umar, may Allah be pleased with them both, used to say that it should be delivered to the ruler?" He said: "Yes. But in my opinion, it is not necessary to deliver it to the ruler."
Hadith Referenceمسند الإمام الشافعي / كتاب الزكاة / 677
Hadith Takhrijفي اسناده مقال من اجل أسامة بن زيد الليثي اخرجه البيهقي: 4 / 115 ۔ وفى المعرفة السنن والآثار له (2418)۔