It was narrated from Ayyub, from Nafi from Ibn 'Umar, who said:"The Messenger of Allah said: 'The two parties to a transaction both have the choice so long as they have not separated or chosen to conclude the transaction." Or perhaps Nafi said: "Or one of them has said to the other: 'Decide! "(Sahih)

English translation · Sunan an-Nasa'i