Red Bull Racing says that it has no intention of being rushed into a decision on its 2019 engine supplier.
The team's current contract for power units with French manufacturer Renault expires at the end of the current season. There's speculation that it might follow its junior Toro Rosso team to the Honda camp next year.
Renault had originally said it wanted an answer about an extension to that agreement in May. The deadline has slipped since then, with Red Bull saying this week a decision would be made by the Austrian Grand Prix on July 1.
This didn't go down well at Enstone, however.
"In Austria, our offer is not going to be there anymore," Renault boss Cyril Abiteboul told Marca this week. "They'll have to talk to Honda."
But Red Bull is refusing to be bounced into a decision before it's ready.
"We're taking a close look in Canada and France," said team principal Christian Horner. "Then we'll make our choice.
The team's motorsports consultant Dr Helmut Marko also sounded irked by Renault's insistence on an early decision.
"Whether it's France or Austria, it's only a few days," he pointed out. "I don't know what's so important about it all of a sudden.
"We will announce our decision between the Grands Prix in France and the race in Austria."
Red Bull were studying Toro Rosso's new Honda engine closely when it made its first race appearance last week in Montreal.
According to Marko, the Japanese company's new power unit represented a significant step forward.
"We're talking about three tenths a lap," he said.
Whether that's enough to tip Red Bull's decision in favour of Honda remains to be seen.