Sebastian Vettel speaking to Sky Sports, says: "Things are different but the atmosphere is good and things are moving in the right way [within the team]. We look forward to starting again, and we really want to get back in and drive but we need to be patient. There's a lot of people working to build these two cars and it's an a honour to drive it so I will do the best I can."

"From the outside it looks different, Mattia Binotto (the new Ferrari team principal) has been around before and he did a good job and continues to do so.

"We have a lot of clever people on board and they continue to do the same job, largely it's not a revolution because Mattia has been here for years and people already know what to expect and how to approach it."

Image source, Reuters

Lewis Armstrong: First day of the F1 season McLaren quietly racking up the laps, surely they haven’t built a reliable car this year??

John Monks: Well I'm colour blind but even I can see that McLaren livery is ocularly offensive. What was wrong with the classic white and red?

Weilong Liang: Can't help but fear McLaren ditching Honda to placate Alonso will hurt the team in the long run as Red Bull climb the timing charts.

Paul Nicholson: They may not have the fastest car this season, but @WilliamsRacing have the best looking car by far!

Looks like toothpaste, don't you think?

If you're wondering what the track looks like when we keep talking about "chicanes", then this should make more sense...

Alistair Knott: Black Haas, wonder how hot it will get in the high temp races?

R. Molloy: Following the #bbcf1 testing coverage while I type up a uni assignment. I'm still getting my head round Sauber becoming Alfa Romeo at such short notice. It's probably going to confuse me all season!

Bob McFeil: The McLaren livery is stunning, the Red Bull is boring and Racing Point looks awful... so no change to last year then!

Andrew Benson
BBC Sport’s chief F1 writer

Williams have suffered a further blow ahead of the new season, with the team saying their car will likely not run until "Wednesday at the earliest".

The problems means Williams are poised to miss at least two days of the eight days of pre-season testing because of delays building the new car.

Deputy team boss Claire Williams said the delay is "extremely disappointing".

Williams finished last of 10 teams in 2018 and were hoping to make progress after internal restructuring.

Read more here.

Image source, Getty Images

And we have some news...

It's lunchtime in Barcelona and the cars are in the garages. So let's be like cricket for once and go for a food break in-between sessions. See you in an hour.

• Kimi Raikkonen goes off on the gravel at turn five causing the first red flag of the session, but with no damage to himself or the car
• Sebastian Vettel spins out of the final chicane, but continues as if nothing ever happened
• Romain Grosjean grinds to a halt with a loss of fuel pressure, causing the second red flag of the session
• Haas, Alfa Romeo, and Red Bull, unveil their new cars and liveries
• Sebastian Vettel leads the timing board, followed by Sergio Perez and Valtteri Bottas

Alex Holland-Martin: Glad to have F1 back. My year can now start.

Moon Quddus: McLaren have their best looking car since the Mercedes/Vodafone days.

Scott Wiseman: I don't understand why everyone is getting angry about liveries not changing, keeps the team recognisable and at the end of the day they are a brand so shouldn't keep changing. They should evolve instead!

Carl Hudson: Why do the @F1 teams bother spending the money and man (people) power to design one off liveries for car launches that the fans LOVE, then just sack them off and revert back to their same old liveries for the season?

1. Vettel 1:18.161 (72 laps)
2. Perez 1:19.944 (20 laps)
3. Bottas 1:20.127 (69 laps)
4. Raikkonen 1:20.160 (46 laps)
5. Verstappen 1:20.176 (52 laps)
6. Sainz 1:20.430 (56 laps)
7. Hulkenberg 1:20.980 (65 laps)
8. Grosjean 1:21.500 (18 laps)
9. Kvyat 1:21.732 (35 laps)

Check out the epic crash at the Daytona 500 yesterday.

Chris Medland
F1 journalist in Barcelona

On Honda's development, Tost says: “I’m very happy. I must say all expectations I put into them they have delivered. I’m quite sure that they will close the gap to the top teams and that Red Bull Racing will be able to win races with them and that we will also gain a lot of advantages out of this cooperation.”

Although Honda's performance improved during 2018, reliability was still an issue. There were numerous grid penalties and retirements throughout the year, but that's not something Tost is expecting to see a repeat of this season.“In 2018 we knew from the very beginning onward that it’s a development process which we have to go through, so this is what we did. In the meantime I think Honda has reached a very high level on the reliability side as well as the performance side, and I don’t expect that we’ll have so many additional engine changes this year. I think first of all we calculate three power units and the rest we will see.”

Image source, Getty Images

Chris Medland
F1 journalist in Barcelona

Max Verstappen has jumped up to second on the timing screens on Red Bull's first day of testing with Honda power, but it hasn't been such a productive morning for Toro Rosso so far.

Just 12 laps for Daniil Kvyat, who returns to F1 this season after a year as Ferrari simulator driver, in the opening three hours - compared to more than 30 for Verstappen. But with a closer technical relationship between Toro Rosso and Red Bull this year, the Toro Rosso team principal Franz Tost is confident both teams are going to be in for a strong season with the Japanese manufacturer.

Image source, Getty Images

Red Bull, yeah same as last year.

Yay or nay?

Image source, Red Bull

Looks like a nice day in Barcelona. A bit different to the snow last year.

Should pre-season testing be back in the desert in Bahrain?

Franz Tost, Toro Rosso's boss thinks so...

Image source, Toro Rosso Twitter

JoeyP: I think this is a master-stroke by Williams... they have realised they have designed a blinder (e.g Brawn) and are sandbagging by not showing up.

Now wouldn't that be incredible. We can only hope! #doublediffuser

Carl Ford:And we're back!!!! It's been a long 3 months but #BBCF1 is back!

YES WE ARE!!!! Bright eyed and bushy tailed and ready for Melbourne in 25 days.

Hands up who thinks Toro Rosso's livery looks just the same as last year?

If it's not broke, don't fix it?

Image source, Getty Images

1. Vettel 1:18.425
2. Verstappen 1:20.174
3. Bottas 1:20.285
4. Perez 1:20.652
5. Raikkonen 1:20.945
6. Sainz 1:21.230
7. Grosjean 1:21.500
8. Hulkenberg 1:21.633
9. Kvyat 1:22.985

Give us a thumbs up or thumbs down on each image, and tweet us via #bbcf1 with a comment. With plenty more to come throughout the day. But first, a timing update.