united opposition front
Political term referring to cooperation among opposition parties, often in elections or legislative battles.
A united opposition front may be realized in the next election.
They oppose the ruling party through a united opposition front.
与党 is the ruling party or coalition, while 野党共闘 refers to the cooperation of opposition parties against it.
野党 is a single opposition party; 野党共闘 is the collaborative effort of multiple opposition parties.
Compound of 野党 (opposition party) and 共闘 (joint struggle). The term became common in Japanese political discourse in the 2010s.