Sheikh Sa`ûd al-Bishr, professor at the Higher Juridical Institute
The one who engages in sexual intercourse with his wife intentionally during the daytime in Ramadan while he has no lawful excuse to break his fast will be obligated to make expiation as follows:
He must fast 60 consecutive days. If he is unable to do so, then he must feed 60 poor people. Aside from this expiation, he must also fast a single day in lieu of the one he missed in Ramadan.
He also has to repent to Allah for the sin that he committed.
Source: Islam Today