Fujifilm said Friday it would increase its investment in a planned biotech plant in North Carolina by $1.2 billion at a time when Japan-US trade ties are in the spotlight.

The cash injection to ramp up output to meet growing demand for antibody drugs brings "the total investment in the facility to over $3.2 billion", the company said.

It plans for the facility to reach full capacity by 2028 and says its total investment will create 1,400 local jobs.

The announcement comes with Japanese Prime Minister Fumio Kishida on a tour to the United States as a state guest.

Marring the mood between Washington and Tokyo at the summit has been President Joe Biden's opposition to Nippon Steel's proposed $14-billion acquisition of US Steel, based in the key election battleground state of Pennsylvania.

A planned visit by Kishida to Toyota and Honda factories in North Carolina on Friday to highlight Japanese investment is seen as an attempt to soothe fears about the deal.

Kishida told reporters in the southern state on Thursday evening that "in terms of economic relations, Japan is the world's largest investor in the US and creates significant employment".

"From tomorrow, I would like to use the visit to see how Japanese companies... are contributing to the US economy," he said, touting "the great importance of promoting investment on both sides in driving the global economy".

Fujifilm announced its original investment in the large-scale cell culture facility in North Carolina, part of its pharmaceutical business, in 2021.

The investment is part of its strategy of enabling the firm "to construct identical large-scale production facilities" in the United States and Europe, it said.