From the Document, "Under Trade Promotion Authority (TPA) procedures, on October 16, 2018, the Trump Administration gave Congress its official 90-day advance notification of intent to enter into trade agreement negotiations with Japan. As the fourth largest U.S. trade partner, Japan is a longstanding U.S. priority for trade negotiations, in particular following U.S. withdrawal from the proposed Trans-Pacific Partnership (TPP) in 2017, which included Japan. With initial TPA requirements met, official negotiations could start at any time. The precise scope of the negotiations remains somewhat uncertain but areas of focus likely include trade commitments on motor vehicles, agricultural goods, services, and potentially policies affecting exchange rates."
CRS In Focus, IF11120
Congressional Research Service: https://crsreports.congress.gov/