Is fasting obligatory for one who did not intend 'Umrah from the Miqat?

Whoever passes the Miqat without entering into a state of ihram for Umrah must offer a sacrifice (dam), which is slaughtering a sheep to be distributed among the poor of Makkah. It is permissible to appoint someone to do this or to pay its value to trustworthy organizations. Whoever is unable to offer the sacrifice should fast instead.