The German is still leading the world championship by a single point, but the momentum has clearly shifted in Mercedes’ direction in the past few races.
Some in the Italian media suspect a new Ferrari ‘crisis’ is on the horizon.
“I don’t think so,” Vettel told La Repubblica.
“I do think Mercedes has recovered a lot of ground, but we are still fast — especially on Sundays.
“On Saturday we suffer too much, because when starting the races from behind it is not always possible to recover.”
Vettel said he expected Ferrari to be slightly stronger at Silverstone recently, but he said there were positives about the performance of the red car.
“In the corners it behaves very well and is balanced. At Copse we were 10kph ahead of them.
“Maybe they are a little more efficient in aerodynamics, which this year counts for much, but in general we are there,” he insisted.
F1 moves to Hungary this weekend for the last race before the August break, but Vettel is not sure it will be a ‘decisive’ weekend.
“I don’t know about decisive, but I do think it will be very different (to Silverstone),” he said.