Toro Rosso and Ferrari have played down media reports that are doing the rounds on Thursday.
A report in Italy suggested that although Toro Rosso will use Ferrari’s 2015-specification engine this year, there is a chance the Red Bull junior team will upgrade to the latest version of the Maranello-built ’power unit’ later in the season.
Both sides moved to dismiss the rumours.
"This is not even an issue for us," Toro Rosso team boss Franz Tost told Speed Week. "I have no idea where it even comes from."
And Ferrari spokesman Alberto Antonini added: "I’ve not even heard of that story.
"It would definitely not be easy to adapt a car to a different engine specification," he said.