Mitsubishi Aircraft has been pushing its regional jet for local government and military use, and according to media reports, a decision could soon be made.
The Japanese reports say the government is looking at purchasing the MRJ regional jet for the prime minister's use on domestic and short-haul international travel.
When contacted, Mitsubishi said the reports are not based on any announcements or comments from the airframer.
"Mitsubishi Aircraft has been promoting the MRJ as the chartered government jets and self defense forces plane since the project launch. Yet we do not have anything specific to announce or comment publicly about this deal from our side," a spokesman said.
"In our view, the MRJ is suitable as the successor for the Japanese self-defense force's [Gulfstream IV aircraft] currently used for middle range government VIP transport," she added.
Flightglobal's MiliCAS database lists the Japan Air Self-Defense Force as having a fleet of five Gulfstream IV aircraft, which it designates U-4. The Japanese government also has two Boeing 747s.
Mitsubishi is working towards the MRJ's first flight target of end-2013 and is conducting sub-assembly of flight test aircraft. Final assembly of aircraft 10001 is expected to start in the next month or so.
Mitsubishi has a backlog of 165 firm orders with 160 options. The programme received a major boost last year when US-based SkyWest Airlines placed an order for 100 MRJ90s with an option for an additional 100 of the type.