The Saudi-led coalition early Saturday launched air strikes "against sources of threat in Sanaa and Hodeida" following attacks by Yemeni Huthi rebels in the kingdom, the official Saudi news agency SPA tweeted.

"The military operation will continue until its objectives are achieved," the coalition said in a statement quoted by SPA.

The Saudi Arabian Formula One Grand Prix will continue "as planned" despite an attack by Yemeni rebels on an oil facility which set off a huge fire visible from Jeddah's street circuit.

Flames ripped through the Aramco oil refinery and drivers even smelt the fire during the opening practice run.

Drivers held nearly four hours of meetings with team bosses and F1 CEO Stefano Domenicali and managing director Ross Brawn into the early hours of Saturday on whether to go ahead with the race. "It's not for me to say, right now," was all Britain's George Russell, representative of the drivers' union, would say, while several team bosses gave assurances that "We race".

"Ready and totally focused for tomorrow's qualy!" Mexican driver Sergio Perez of Red Bull tweeted after the meetings ended at 2:20 am, apparently confirming the decision to race on Sunday.

Domenicali had earlier insisted the weekend would continue as planned.

"Formula 1 has been in close contact with the relevant authorities following the situation that took place today," an F1 spokesman said after the second practice session at 9:00 pm.

"The authorities have confirmed that the event can continue as planned and we will remain in close contact with them and all the teams and closely monitor the situation."

- 'I smell burning' -
Domenicali and Mohammed Ben Sulayem, the newly elected president of the sport's ruling body the International Motoring Federation (FIA), met with drivers and team bosses to try to reassure them.

"We have received total assurance on safety and security here, for the country and for the families," Domenicali said after this first meeting. 

"We have all put safety first to protect this area and the city where we are going," he said.

"The question is who are these rebels targeting? It is the economic infrastructure not civilians and not this track. We have high level assurance that this is a secure place and nothing is going to happen," added Ben Sulayem.

World champion Max Verstappen was one of the first drivers to be aware of the drama unfolding while he guided his Red Bull through the first practice session.

"I smell burning –- is it my car?" said the Dutchman on his team radio.

Friday's attack was part of a wave of assaults ahead of the seventh anniversary of a Saudi-led coalition's military intervention against the Huthis in Yemen, a country in the grips of a major humanitarian crisis.

The coalition fighting the Iran-backed rebels confirmed the Jeddah oil plant attack.

"They are trying to impact the nerve-centre of the world economy," the coalition said in a statement. 

"These attacks have no impact on life in Jeddah," it added.

Early Saturday the coalition said it had carried out retaliatory strikes against Yemen's Sanaa and Hodeida.

- 'Safety main priority' -
Meanwhile, on the track, Charles Leclerc topped the final practice times for Ferrari ahead of Verstappen.

The 24-year-old Monegasque driver and early-season leader of the embryonic championship clocked a best lap in one minute and 30.074 to outpace the Dutchman by nearly two-tenths.

Carlos Sainz was third in the second Ferrari and Sergio Perez fourth, with a determined Lewis Hamilton fifth ahead of his new Mercedes team-mate George Russell after a day of bumping and sliding on the high-speed circuit.

After a 15-minute delay to the second practice session, Leclerc, who won the season-opener in Bahrain last week, picked up where he had left off in opening practice by setting the early pace again.

Both Sainz and Hamilton complained of "porpoising" before the two Red Bulls joined the action, Verstappen going third but more than a second off the leading pace.

Verstappen then clocked the top time, 0.002 ahead of Leclerc as most of the field moved to soft tyres, the Monegasque reclaiming his perch with a lap in 1:30.074, nearly two-tenths quicker.

Shortly after this, Kevin Magnussen reported an engine problem with his Haas and came to a halt at Turn 14. 

That brought a brief Virtual Safety Car (VSC) deployment before, on resumption, Leclerc clipped a wall with the left front wheel of his Ferrari.

He trundled back to the pits and out of the session just as the race promoters Saudi Motorsport issued a statement confirming the Grand Prix would go ahead as planned.

"The safety and security of all our guests continues to be our main priority and we look forward to welcoming fans for a weekend of premium racing and entertainment," they said.

Ferrari also issued a statement to confirm that both Leclerc and Sainz had been "kissing the wall" and were out of the session due to damage. 

Friday's attack comes as the Saudi authorities continue to face accusations of trying to "sportswash" the country's controversial human rights record.

Drivers say they are "aware of the problems", said McLaren's Daniel Ricciardo.

"But I think by coming here we also have a chance to create change or have a positive influence." 

Seven-time world champion Lewis Hamilton added: "We don't decide where we go, but we're duty-bound to try and do what we can while we are here."