Sainz, who shares a name with his world rallying legend father, is the current cream of Red Bull's junior driver programme, and hotly tipped to replace Jean-Eric Vergne at Toro Rosso in 2015.
But in the wake of F1 backmarker Caterham's takeover, new team advisor Colin Kolles had talks at Silverstone with Sainz jr and snr and Red Bull's Dr Helmut Marko.
It is believed a deal whereby Sainz jr makes his F1 debut in a green car this year, replacing Kamui Kobayashi, was discussed, possibly with the forgiving of Caterham's gearbox bills to Red Bull as payment.
According to some Spanish reports, the parties failed to agree.
"Yes, it is true that there have been talks with them (Caterham)," Sainz jr told the Spanish daily AS, "but there is nothing confirmed.
"It doesn't change anything for me because my goal remains the same: to be at Toro Rosso in the future," he added.
"If for that to happen I pass through Caterham then I do so happily. It has been possible to race this year, but Red Bull is the one who decides. They and Caterham must also benefit and reach an agreement."
If Marko and Kolles ultimately shake hands, Sainz's F1 debut would be similar to the impressive Daniel Ricciardo's in 2011, when the Australian drove for the Kolles-run HRT team before switching to Toro Rosso.
"Getting F1 kilometres under your belt always helps," Sainz said, "no matter how good the team is.
"If they have considered it for me, it's a good sign that I'm doing things right."