"When this verse- 'And warn your tribe (O Muhammad) of near kindred'- was revealed, the Messenger of Allah said: 'O Fatimah, daughter of Muhammad! O Safiyyah bint 'Abdul-Muttalib! O Banu 'Abdul-Muttalib! I cannot avail you anything before Allah; ask me for whatever you want of my wealth.'"
Sunan an-Nasa'i Book 30, Hadith 38