Trading volume in Japan’s power futures is set to climb as companies prepare for expiration of a key agreement between the nation’s largest utilities, a change expected to jolt the market.

After months of fraught negotiations with the United States, Japan clinched a deal just days before punitive tariffs were scheduled to take effect.

Trump said the U.S. and Japan had struck a trade deal that includes a lower 15% tariff that will be levied on U.S. imports from the country, including autos.

Prime Minister Shigeru Ishiba is under increasing pressure to bow out after his party and junior coalition partner Komeito lost their majority in Sunday's election.

This means that Ishiba no longer has easy control over the upper or lower houses of parliament; last October, the LDP lost control of the more powerful lower chamber, marking a major upset for a party that has ruled Japan for most of its post-World War II history.