Herta lacks the necessary points and would need a special dispensation from the governing FIA, with some teams unhappy about that.
The American is in the frame to replace Frenchman Pierre Gasly (26), now considered the front-runner to replace double world champion Fernando Alonso (41) at Renault-owned Alpine when the Spaniard moves to Aston Martin.
"We just need clarity on what is the situation regarding driver points which hopefully will come sooner rather than later," Red Bull team boss Christian Horner told reporters at the Dutch Grand Prix.
"That plays a key role obviously in the driver merry-go-round."
Horner said Red Bull would not release Gasly from his 2023 contract "if we don't have something exciting to put in that (AlphaTauri) car" but also described Herta as an "exciting talent".
"He’s a young American, a guy that’s been a standout talent in the US so it’ll be very interesting to see how he performs in Formula One," he added.
"Formula One obviously has got growing popularity in the US market at the moment and to have a successful US driver could be very interesting, could be interesting for us in the longer term."
Andretti Autosport driver Herta tested a 2021 Formula One car with McLaren in Portugal last July and told reporters then that he felt fast enough to make the switch.
AlphaTauri is a feeder team to Red Bull Racing, whose world champion Max Verstappen (24) started out there when the team raced as Toro Rosso.
Seven times race winner Herta is already the youngest IndyCar driver to triumph in a series that features cars without power steering and capable of doing more than 370kph.
A GROWING MARKET
The United States is a growing market for Formula One, whose commercial rights are owned by US-based Liberty Media, and will have three races next year including a new night-time Grand Prix in Las Vegas.
Formula One last had a US driver in 2015, with Alexander Rossi.
Drivers need 40 points to qualify for a super-licence but Herta currently has only 32 and cannot make up enough points this season.
"If we don't respect our own rules and try to find ways around it I don't think that's correct," Haas team boss Guenther Steiner said at the weekend, while adding he was supportive of changing the points allocation in future.
"There are quite a few (IndyCar) drivers who have got a super-licence. I think Alexander Rossi and Josef Newgarden, they have got super licences you know, and they did that within the rules."
Mercedes boss Toto Wolff agreed: "It would be great to have an American in F1 and it obviously would give us a good boost ... but I think the points system is there for a reason," he told reporters.
"The regulations are the regulations, and I would really hope the Americans can somehow score enough points to make it in F1."
