The current Minister of Family, Manuela Schwesig, calls on the Conservative Party to stop its opposition to the question:
"It's time for the conservatives to move on this issue. It must stop putting the brakes on modernization," she told Reuters.
German Chancellor Angela Merkel is the leader of the government since 2005 and a member of the Conservative Party. She has opposed the equal marriage law in recent years, preventing its approval.
Germany will hold elections next September and the issue of marriage equality could play an important role.
Indeed, the population, as usual, is in favor of marriage for same-sex couples.
According to a study by the Federal Anti-Discrimination Agency, 83% of Germans support equal marriage.
The Green Party is already supporting this attempt. The Social Democratic Party plans to launch it at a coalition meeting.
A coalition, two parties (conservatives and social democrats), forms the German government.