They said in a joint statement that an Andretti Cadillac team, if accepted by Formula One and the FIA governing body, would be based in the United States with a support facility in Britain.
"The Andretti Cadillac team is planning to submit an expression of interest when the FIA opens the formal process," the statement added.
"If selected, the team is seeking to compete as soon as practical with at least one American driver."
Andretti Autosport's IndyCar driver Colton Herta (22) would be a frontrunner for a seat.
FIA President Mohammed Ben Sulayem said the governing body was exploring the expressions of interest process and would provide an update soon.
He said the process would follow strict protocols and take several months.
Formula One insiders saw no chance of a new team before 2026, when a new power unit is due to be introduced and Audi are set to enter a factory team after taking over Swiss-based Sauber.
The last completely new team to enter Formula One was US-owned Haas in 2016.
"We've done a lot of hiring, we have quite a few people working for us, we have hired the main engineers so we are very much down the road," Michael Andretti told reporters on a video conference.
"We have our technical director already hired and we will announce that down the road.
"One of the things is to have an American manufacturer behind and an American team with an American driver. I think it is going to be the biggest story of the year.
"The great thing is that GM has great people and resources at the ready so that is going to help us get up and running even quicker so we are in a really good position right now."
Andretti, who already has interests in IndyCar, Formula E, Extreme E and sportscars, announced plans for an F1 entry last February but met a lukewarm response at the time from the FIA.
He has also met resistance from many of the existing 10 teams, as well as Formula One management, who have questioned the commercial benefit of a new entrant diluting the share of revenues.
Any new entrant must currently pay a $200million fee to enter, with that money shared by the existing teams as compensation.
"Today's news from the United States is further proof of the popularity and growth of the FIA Formula One world championship," said Ben Sulayem.
"It is particularly pleasing to have interest from two iconic brands such as General Motors Cadillac and Andretti Global."
Andretti are not the only ones exploring potential involvement in the sport, with Honda also reportedly mulling a comeback, and Formula One said there were "a number of conversations continuing that are not as visible as others.
"We all want to ensure the championship remains credible and stable and any new entrant request will be assessed on criteria to meet those objectives by all the relevant stakeholders," a spokesman said.
"Any new entrant request requires the agreement of both F1 and the FIA".
Formula One will have three US races this year, with a debut in Las Vegas, and a US driver with Logan Sargeant (22) a rookie with Williams.
