Daniel Ricciardo is upbeat about the future after testing Renault's highly-anticipated engine upgrade in Barcelona.

The Australian admitted to being "bitter" last Sunday, when his brand new teammate Max Verstappen sensationally ended Red Bull's winning drought at his first attempt.

"It's frustrating - I think we just threw the win away," Ricciardo had said after the race, referring to his three-stop strategy versus Verstappen's two.

"I'm bitter right now. Not with Max, not at all, just bitter at the situation."

"So far everything looks quite good," he said on Tuesday, as Renault got to work on a significant engine upgrade that is reportedly 35 horse power up and an almost half a second boost on the earlier specification.

"The engine was reliable and the step is noticeable," Ricciardo added.

Esteban Ocon, who drove the works Renault in Friday practice last week, agrees that the new engine is a step forward.

The French teen tested the yellow car on Tuesday and observed: "The engine is really good, significantly better. You can feel the extra power."

Renault has pencilled in Canada for the debut, but there are suggestions the engine could actually be raced for the first time in Monaco, where Red Bull is expecting a highly competitive race.

"We will use it where we can and it would be great if it is in Monaco, but we'll have to wait and see," Ricciardo is quoted as saying by De Telegraaf newspaper.

Ricciardo is currently fifth in the driver rankings after the first five races of the year.