Perez beats Veratappen by 0.346s to take top spot. Impressive lap from the Mexican.
A 1m36.456s puts Verstappen top now, 0.4s ahead of Alonso.
Leclerc, Norris and Stroll complete the top five.
A 1m36.886s puts Leclerc on top of the pile, less than a tenth ahead of Norris.
A 1m37.492s, 0.5s ahead of teammate Zhou.
Bottas' time is soon beaten by Hamilton- by just over 0.2s.
"Some light drops of rain," he reports.
SQ1 kicks off - a 12 minute session with drivers required to run on the mediums only.
FIA note a 60 per cent chance of rain for sprint qualifying.
SQ1: 12 mins in length - new medium tyres only
SQ2: 10 mins in length - new medium tyres only
SQ3: 8 mins in length - soft tyres only
Next up we have qualifying for the sprint race at 8:30am UK time!
Stroll, Piastri, Verstappen, Perez, Hulkenberg, Magnussen, Ocon, Albon, Ricciardo and Bottas.
Looks like Stroll is going to top the session here in FP1.
Stroll takes to the top now for Aston Martin, 0.3s ahead of Piastri.
Norris was on course to go 0.4s clear at the top of the timesheets but he returns to the pit lane.
Not sure we were expecting that... he sets a 1m36.629s to topple Verstappen.
He goes third-fastest in the upgraded Alpine.
Verstappen, Perez, Albon, Ricciardo, Bottas, Zhou, Tsunoda, Leclerc, Sainz and Sargeant is the top 10 currently.
It's a 1m36.660s for Verstappen, just under 0.5s clear of Perez.
Albon is the latest driver to make the most of the softs, storming to the top of the order.
Sargeant slots into second on the softs. As we enter the final 15 minutes, expect plenty of qualifying simulations.
Alonso goes down the escape road on the entry of the pit lane before spinning around to get back going again.
The current order is: Leclerc, Sainz, Verstappen, Perez, Ocon, Norris, Russell, Hulkenberg, Hamilton and Alonso.
He lowers his benchmark to a 1m38.090s, 0.3s ahead of teammate Sainz. Lower down the field, Russell slots into sixth.