It is narrated from Sayyiduna Hayyan Abu Imran al-Ansari (may Allah be pleased with him): The Messenger of Allah (peace and blessings be upon him) delivered a sermon on the day of Khaybar, "and he forbade them from selling any share of the spoils before it is distributed, and from having intercourse with pregnant slave-women until they give birth, and from selling fruit until its ripeness becomes evident and it is safe from blight."
Duhaym added in his narration: "And he (peace and blessings be upon him) made lawful for them three things which he (peace and blessings be upon him) had previously forbidden them: (keeping) the meat of sacrificial animals (beyond three days), visiting graves, and using (all kinds of) vessels."
Hadith Referenceالمعجم الكبير للطبراني / باب الحاء / 3560