The Constitutional Democratic Party of Japan, the largest opposition party in parliament, submitted a bill to the Lower House on Wednesday that would allow married couples to retain different surnames ¡ª the first step in what¡¯s set to be a long debate over the next two months.

The party will now attempt to coalesce a united front against the ruling coalition in cooperation with other opposition parties. However, a clear divide emerging within the opposition camp suggests that further compromise might be necessary on the road to approval.

The CDP¡¯s bid reflects the party¡¯s endeavors to find some common ground with other actors in parliament, CDP Upper House lawmaker and party acting leader Kiyomi Tsujimoto told reporters after the bill¡¯s submission.