"Rather than drafting a document, we would like the president to issue an executive order quickly and implement the 15% tariff rate," said Ryosei Akazawa, Japan's top trade negotiator, at a press conference on Tuesday.
The two sides agreed last week to lower "reciprocal" tariffs put in place by U.S. President Donald Trump on Japanese goods to 15% from the planned 25%, and total import duties on autos to 15% from 27.5%.
Trump is known to suddenly change his mind on policies. Akazawa told public broadcaster NHK on Saturday that if a written bilateral agreement were to be drawn up, Trump would be asked repeatedly by his cabinet members to confirm details, increasing the chances of him changing the deal.
"What Japan gets from the deal is definite, and what Japan is offering is being left vague," said a Japanese government source. Since the tariff reductions won through many rounds of negotiations won't be complicated by differences in interpretation, crafting a written agreement may not be in Japan's best interest.
At the same time, Japan has pledged to invest in the U.S. and purchase U.S. products, and the two sides differ in how they explain this proposed arrangement.
The U.S. has said that Japan will invest $550 billion at Washington's direction. Tokyo, meanwhile, says the figure applies to a framework for investment, loans and loan guarantees from state-backed financial institutions. Akazawa told NHK that investment would account for around 1% to 2% of the total.
Creating a written agreement could force Tokyo to agree to the U.S.'s terms, and would also clarify Japan's obligations. On the other hand, without a written agreement, there is a risk that the U.S. will not abide by the terms of the deal.
"Even if there is a written agreement, the U.S. right now is a country that would not hesitate to break it," said Kazuhisa Shibuya, a professor at Kwansei Gakuin University who was involved in negotiations on the 2019 U.S.-Japan Trade Agreement as part of the Cabinet Secretariat. "There is no need to go to the trouble of putting it in writing and clarifying Japan's obligations."
There are also risks associated with leaving the agreement vague.
"If Japan doesn't stick to the terms of the deal, tariffs will go back up," said Treasury Secretary Scott Bessent in an interview with Fox News on July 23. "We'll evaluate it every quarter and if the president is unhappy, then they will boomerang back to the 25% tariff rate both on cars and the rest of their products."
Japanese officials are also struggling to explain the deal to the public, given the lack of a written agreement and some comments from U.S. officials.
"This is literally the government of Japan giving Donald Trump and the American people $550 billion to invest at his direction on things that are important to America and national security," U.S. Secretary of Commerce Howard Lutnick told Fox News on July 23.
His statements suggest that a huge sum of Japanese taxpayers' money will be invested in the U.S. -- something far removed from Japan's understanding of the agreement.