Hamilton on top in opening practice

Just 24 hours after the pair had been instructed to obey a revised 'code of engagement' following three collisions in five races, the 31-year-old Briton clocked a best lap in one minute and 31.654 seconds.

Mercedes' Lewis Hamilton during practice at Silverstone on Friday.

World champion Lewis Hamilton grabbed the initiative on Friday morning when he narrowly outpaced championship leading Mercedes team-mate Nico Rosberg to top the times in opening practice for this weekend's British Grand Prix.

Just 24 hours after the pair had been instructed to obey a revised 'code of engagement' following three collisions in five races, the 31-year-old Briton clocked a best lap in one minute and 31.654 seconds.

This lifted him clear of German Rosberg by just 0.033 seconds and left third-placed Nico Hulkenberg of Force India eighth-tenths adrift ahead of compatriot Sebastian Vettel of Ferrari.

Australian Daniel Ricciardo was fifth for Red Bull ahead of Finn Kimi Raikkonen, whose future with Ferrari was settled earlier Friday when the team said he had been re-signed for 2017.

On a cool and overcast morning at the former airfield circuit in central England, Dutch teenager Max Verstappen was seventh in the second Red Bull ahead of Sergio Perez of Force India and Spaniards Carlos Sainz of Toro Rosso and two-time champion Fernando Alonso of McLaren.

The embattled Mercedes men dominated the session, trading fastest times throughout before Hamilton - warmly applauded by his home crowd - settled on top.

Vettel ended the session with gearbox problems as he coasted back to the pits. He began the morning with a test run of his car using the latest 'halo' cockpit protection device that is in line to be introduced to Formula One next year.