"We can't accept that bishops continue to impose their moral position on the [Spanish] people," Elena Valenciano, the vice president of Spain's opposition socialist PSOE party said.
Valenciano also said the party will downgrade its relations with the Vatican if more rules are introduced, The Local.es reported.
Justice Minister Alberto Ruiz-Gallardon announced plans to change the country's abortion law Monday.
The announcement came one day after Prime Minister Mariano Rajoy met with Pope Francis at the Vatican.
Possible changes under discussion include banning abortions for those under age 18 without parental permission, as well as making abortions illegal when the fetus is deformed, The Local.es said.