Nico Hulkenberg has turned down an offer to drive for McLaren in the British marque's first full Indycar season next year.
"I have a lot of respect for those who race on ovals, it's just not my thing," said the German, after McLaren boss Zak Brown revealed the failed talks in Singapore.
Earlier, the Renault refugee had also ruled out Formula E, saying the all-electric series is "not exactly exciting".
"Formula 1 blood flows in my veins," Hulkenberg insisted.
The 32-year-old has already missed out on the Haas seat, and Antonio Giovinazzi looks set to keep his Ferrari-promoted seat at Alfa Romeo.
Giovinazzi's father Vito has apparently been telling people in the paddock that his 25-year-old son has already signed up for 2020.
"Don't ever believe a father," Hulkenberg laughed.
"They sit here all day, talking and drinking a little and talking a little more.
"I'm calm. Let's see what happens," he added.
"Hulkenberg is hard to imagine for Red Bull," Marko told Germany's Motorsport-Magazin.com in Singapore. "We look at the external options, but no one would be a significant improvement."
Hulkenberg told Sky Italia: "There is still a realistic possibility of staying in Formula 1.
"It's difficult to talk about specifics, because as you can imagine that's private details. But everyone knows what places are available.
"Right now I am still totally focused on Formula 1."body check tags ::