Leclerc finished FP2 in 10th and couldn’t quite get things to work around the track whilst Lewis Hamilton topping the timesheet in both sessions.
"It was very difficult, particularly in FP2, as some things were not working on my second run," Leclerc said (quoted by GPFans.net).
"This is no time to panic but we're clearly behind Mercedes. [They are] out of reach for us, so we have to focus on what we have to do, find the best solutions for our car and then we'll see.
"The target is to improve and close the gap. It will be very difficult to get to the front row of the grid but nothing is impossible until qualifying is over.
“We'll work to improve quite a lot. To be honest from now we are working to close the gap, so we don't know yet what we need to do.”
One of the problems Ferrari have had in competing with Mercedes is maintaining a higher speed in low-speed corners, somewhere the Silver Arrows have seemed to excel so far this season.
Leclerc said: "We expected [Mercedes] to be strong here because they were very strong in the low speed corners in Barcelona for example, but we need to focus on ourselves, try to put these tyres in the right window - which we don't do at the moment - and then we'll see."