The German is 17 points behind Mercedes' Lewis Hamilton, the championship leader, but is favourite to win Sunday's Italian Grand Prix.

"Everyone can feel something special is going on. We have a good car but we need to make it happen," said Vettel.

Meanwhile, Lewis Hamilton arrived late because of what Mercedes said was an "unavoidable personal commitment".

The world champion missed all his media and public commitments on a day largely set aside for such events.

Mercedes declined to elaborate further beyond saying he would be in Monza on Thursday evening and his weekend would "proceed as normal from there".

Hamilton has a 17-point lead over Vettel with eight races of the season after the German's win in Belgium last Sunday.

Vettel, who suffered a minor crash in the F1 Live event in Milan on Wednesday, acknowledged that Ferrari were "going in the right direction" but he emphasised that Mercedes "is still very strong".

He added: "It is good to see we are getting stronger. In some areas, we have caught up. In others maybe we have a little bit of an edge. That is where we want to be, and maybe even beyond that.

"We want to keep that level through the year, and if there is a gap to increase it. It is going in the right way but there are a lot of things that can be improved and we need to focus on those and go step by step.

"It is a great feeling when you can fight for pole and victory. It is what you want."

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Hamilton was comfortably beaten by Vettel in Spa after the Ferrari passed him down the straight on the first lap of the race, and Mercedes F1 boss Toto Wolff said afterwards that the Italian team now had a power advantage over Mercedes.

Hamilton said he felt that Mercedes' biggest deficit was a lack of traction out of the slow corners that precede the longest straights at Spa.

The Briton added that he hoped the different layout of Monza, where he dominated last year after a close fight with Vettel in Belgium, would better suit the Mercedes.

Speaking on Sunday after the Belgian Grand Prix, he said: "Luckily, apart from Turn One, it is not that slow there, so I am hoping the traction loss we are having in these super-slow corners won't be as bad there."

Wolff added: "The last race where we have been quickest in pure pace was Silverstone [in early July]. Since then, Ferrari have been quicker.

"Monza was a good one [for Mercedes last year], so I am very curious to see how it is going to go in Monza.

"Last year we were very much in control of the whole weekend. Ferrari had their worst weekend of the whole season performance-wise.

"I am not worried. I think we should still address the opportunities that exist within our car where we need to optimise and only that will make us win the championship."