Red Bull advisor Helmut Marko has revealed that the team could stay with Renault beyond next season.
The four-time constructors' champions had been involved in a public spat with the French supplier after suffering from a lack of performance in 2015 and often finishing well off the pace of the dominant Mercedes car.
Red Bull are now expected to keep Renault power units next year and Marko has opened the door for that partnership to continue beyond 2016.
He told Speedweek: "We still hope to secure an alternative engine from 2017, but the other option would be that Renault develops its power unit so well during the 2016 season that we can consider continuing to work with them.
"We will have the same engines as the new Renault works team. Mario Illien will cooperate with his Ilmor company as a consultant with Renault to help develop the power unit.
"They have presented concepts that look good. Now these need to be implemented and deliver in practice what has been promised in theory. The question is how quickly that will be possible."
Red Bull were also believed to have struck a deal with Mercedes before Toto Wolff vetoed the arrangement.