Nippon Ishin no Kai (Japan Restoration Party) and Your Party will cooperate in this summer’s Upper House election by not running candidates against each other in the same district.

However, Your Party officials have ruled out for now a merger with Nippon Ishin, despite growing pressure from Nippon Ishin coleader Osaka Mayor Toru Hashimoto.

The accord, reached Wednesday in Tokyo between Nippon Ishin Secretary General and Osaka Gov. Ichiro Matsui and Your Party Secretary General Kenji Eda, means the parties will coordinate in fielding single-seat candidates nationwide.

Nippon Ishin is considered strong in Kansai and western Japan, especially Kyushu, while Your Party’s strength lies in the Kanto region and eastern Japan, raising the possibility the parties will emphasize regional rather than national issues.

Eda added that merging the two parties, a long-stated desire of Hashimoto, isn’t going to happen, at least not yet.

“First, we have to reach agreement on basic policy,” he said.

There are several fundamental areas, such as nuclear power and the Trans-Pacific Partnership agreement, where Your Party differs with Nippon Ishin’s leaders, most notably coleader Shintaro Ishihara. Your Party strongly favors getting out of nuclear power and joining the TPP. But Nippon Ishin has offered only lukewarm support for pulling the plug on nuclear power and is willing to join the TPP only if it doesn’t harm undefined domestic interests.