With more than an hour still to run, Leclerc set the fastest time of 1:31:750, with Oscar Piastri half a second behind.
Williams' Logan Sargeant rounded out the top three, with Sergio Perez in fourth and Fernando Alonso in fifth.
Below is the full classification from the morning session on Thursday:
1. Charles Leclerc (Ferrari) - 1:31.750 36 laps
2. Oscar Piastri (McLaren) - +0.578s, 35 laps
3. Logan Sargeant (Williams) - +0.828s, 30 laps
4. Sergio Perez (Red Bull) - +1.129s, 20 laps
5. Fernando Alonso (Aston Martin) - +1.303s, 31 laps
6. Lewis Hamilton (Mercedes) - +1.475s, 39 laps
7. Zhou Guanyu (Kick Sauber) - +1.965s, 38 laps
8. Pierre Gasly (Alpine) - +2.054s, 33 laps
9. Nico Hulkenberg (Haas) - +5.759s, 31 laps
10. Yuki Tsunoda (Visa Cash App RB) - +6.324s, 40 laps
Williams' Logan Sargeant rounded out the top three, with Sergio Perez in fourth and Fernando Alonso in fifth.
Below is the full classification from the morning session on Thursday:
1. Charles Leclerc (Ferrari) - 1:31.750 36 laps
2. Oscar Piastri (McLaren) - +0.578s, 35 laps
3. Logan Sargeant (Williams) - +0.828s, 30 laps
4. Sergio Perez (Red Bull) - +1.129s, 20 laps
5. Fernando Alonso (Aston Martin) - +1.303s, 31 laps
6. Lewis Hamilton (Mercedes) - +1.475s, 39 laps
7. Zhou Guanyu (Kick Sauber) - +1.965s, 38 laps
8. Pierre Gasly (Alpine) - +2.054s, 33 laps
9. Nico Hulkenberg (Haas) - +5.759s, 31 laps
10. Yuki Tsunoda (Visa Cash App RB) - +6.324s, 40 laps
