Prime Minister Mariano Rajoy came to power in 2011 promising to change a more liberal abortion law passed the previous year by the then Socialist government.
Rajoy's conservative Popular Party and the Roman Catholic Church have hotly opposed the 2010 abortion law, which allows abortion up to 14 weeks of pregnancy or up to 22 weeks if the foetus is deformed.
Now the government seems set to return Spain to the earlier 1985 law, which decriminalized abortion only in cases of rape, deformation of the foetus or serious physical or psychological risks to the mother.
The new law to be presented before the end of October will be "in line with our commitments and with the criteria of the Constitutional Court," Justice Minister Alberto Ruiz Gallardón told public radio RNE.
The Constitutional Court has ratified the 1985 law but has not yet ruled on a Popular Party appeal against the 2010 abortion reform.
Spain's ruling party has agonized over the reform, with the justice minister at one point surprising even members of his own party by saying that a risk to the mother should not be considered as a "pretext for not protecting a newborn".