Lewis Hamilton stamped his early authority on proceedings for Mercedes by topping Practice 1 in drying conditions at the United States Grand Prix.

Morning rain resulted in a damp track at the Circuit of the Americas, forcing all drivers to run on the intermediate tyres but gradually a dry line emerged with the Briton posting a 1:36.335s as he starts a weekend that could see him claim a fourth Formula 1 title.

Based on the early pace, however, those chances do seem as "silly" as the 32-year-old suggested on Thursday with main rival Sebastian Vettel second for Ferrari just pipping the other Silver Arrow of Valtteri Bottas, with the Finn in third.

The first 90 minutes of running would be dominated by the crossover from inters to slicks with Hamilton setting the pace in the wet albeit only marginally in front of Max Verstappen and Vettel.

It would be the German who was the first to use the dry rubber and would immediately improve the best time by some five seconds as much of the circuit dried out sufficiently.

Damp patches in the final sector would stop most from heading out, however, and it wasn't until Daniel Ricciardo emerged and went another five seconds faster which triggered the rest to start some meaningful running.

The top teams would opt to use the red-marked Supersoft tyres in the final 30 minutes or so with Hamilton, Vettel, Bottas and Verstappen in fourth, all on that compound.

Stoffel Vandoorne and Felipe Massa would be the only top 10 drivers to use what are pink-striped Ultrasoft Pirellis for this weekend as they claimed fifth and sixth respectively.

Kimi Raikkonen would be seventh in the second Ferrari with Esteban Ocon, who was one of three drivers to spin in the damp early on, and Sergio Perez using the Soft tyres as the two Force India's were eighth and ninth.

Carlos Sainz would complete top 10 in his first session for Renault, some eight-tenths clear of new teammate Nico Hulkenberg. Kevin Magnussen would be 11th for home team Haas with Canadian Lance Stroll 12th for Williams.

In his first F1 session with Toro Rosso, Brendon Hartley would be a solid 14th and a long way clear of Sean Gelael as the Indonesian completed another P1 run with the junior Red Bull team.

Daniel Ricciardo would have a tricky session, spinning in the wet and ending his session early to complete setup changes to his Red Bull, leaving the Australian only 16th fastest.

At Sauber, Charles Leclerc would complete his second outing for the Swiss team ending less than four-tenths behind Marcus Ericsson as Fernando Alonso brought up the order as he didn't set a time in his McLaren due to a hydraulics leak.