George Russell and Mercedes posted the fastest time during Friday morning's session at the Circuit de Barcelona-Catalunya.
Russell's benchmark time of 1:19.233 on the Soft C5 tyre put him half a second clear of Red Bull's Max Verstappen, who used the Medium C3s.
There were several red flags, with Fernando Alonso, Pierre Gasly and Guanyu Zhou all caught up in incidents.
The full times and tyre compounds are listed below.
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