The US will secure 90 per cent of profits from joint investments with Japan only if it takes on a proportional amount of risk and financing, Tokyo said on Friday, as cracks widened in the two allies’ interpretation of their hastily agreed trade deal.

Japanese officials said there was no written agreement with Washington — and no legally binding one would be drawn up — after Trump administration officials claimed Tokyo would back investments in the US from which American taxpayers would reap nine-tenths of the profits.

Japan secured a reduction in reciprocal and automotive tariffs from US President Donald Trump’s threatened level of 25 per cent to 15 per cent in the deal announced this week, but sharply different perceptions of what was agreed have since become apparent.