Colin Kolles has confirmed that a technical partnership with Toyota’s former Cologne-based F1 team is an "option" for Hispania.
At Hockenheim on Friday, HRT driver Bruno Senna indicated the two parties are in talks but insisted that no agreements are signed yet.
A Toyota Motorsport spokesman also would not confirm the reports.
"Toyota is an option," HRT team boss Colin Kolles is quoted by Spain’s AS newspaper at Hockenheim.
"I think it might be good for us," he added.
Reports said the HRT/Toyota deal would involve use of Toyota’s Cologne headquarters, staff and designs of the unraced 2010 car.
Before the money arrives from Spain, Toyota is reportedly rehiring engineers including by publishing announcements in specialist magazines.