Prime Minister Shinzo Abe held a meeting Thursday with Spanish King Felipe VI and Queen Letizia, who are visiting as state guests to strengthen bilateral ties.
While the king and queen serve a symbolic rather than a political role in their country, the meeting at the Government Guesthouse in Akasaka offered them an opportunity to discuss the aims of their trip.
The previous day, the foreign ministers of Japan and Spain met in Tokyo and agreed to cooperate on cementing a broad agreement on free trade between Japan and the European Union as the negotiations continue.
The royal couple's four-day visit, which was to end Friday, came ahead of the 150th anniversary next year of the establishment of bilateral relations between Japan and Spain.
The king ascended the throne in June 2014 following the abdication of his father, King Juan Carlos I. He visited Japan three times before becoming king.