Red Bull team principal Christian Horner is eyeing an improved performance this year after a "big winter" for engine supplier Renault.
Red Bull emerged as Mercedes' main rivals in 2016, but have some way to go to knock them off their perch.
"It's a brand new engine this year, a change of philosophy," said Horner. "They've had a big winter.
"We're hoping for a step in performance, and if that's delivered then hopefully we can really be a challenger this year and give Mercedes and Ferrari a hard time.
"Mercedes, they're the triple world champions, the team to beat.
"They set the bar pretty high. That's what we're aspiring to.
"The driver line-up we have is fantastic, we've had great stability in the team, and we're excited about the year ahead."