Lewis Hamilton made a pointed attack on Ferrari after the British Grand Prix in which the Mercedes driver was able to finish only second having been hit by Kimi Raikkonen on the opening lap.

It is the second time in three races the teams have clashed while racing and Hamilton suggested they had not been merely accidents. His claims were dismissed by the race winner, Sebastian Vettel, as “silly” and “unnecessary”.

The world champion started from pole but was slow off the line and was nudged into a spin by Raikkonen at turn three. Hamilton put in a strong recovery drive from the back of the field, meaning Vettel had to settle for extending his championship lead from one to eight points but the Mercedes driver was still not happy.

Vettel hit Hamilton’s team-mate Valtteri Bottas at the French Grand Prix and Hamilton considered the incidents together after the race at Silverstone. “Interesting tactics, I would say, from their side,” he said on the podium.

He went further, when asked if he was suggesting the incident at turn three had been deliberate, he replied: “It’s now two races that the Ferraris have taken out one of the Mercedes.” It is a threat the four-times world champion believes is very real.

“We’ve just to work hard to try to position ourselves better so that we are not exposed to the red cars,” he said. “Because who knows when that’s going to happen again. We’ve got to make sure we work hard together as a team to try to lock out the front row and make sure we’re fully ahead of these guys.”

Vettel was dismissive of any suggestion either incident had been intentional. “It’s quite silly to think that anything that happened was deliberate,” he said.

“I would struggle to be that precise, to take somebody out. In France, I lost my wing so I screwed my race. I think it’s easy to attack and have a great move and also easy to have an incident. I don’t think there was any intention and I find it a bit unnecessary to even go there.”

His team-mate Raikkonen admitted he had been at fault but insisted it was a racing incident. “Things happen sometimes,” he said. “Unfortunately we touched and both paid the price. It’s easy to say after the couple of races that we’re suddenly doing something against them but we’ve been hit very many times ourselves, so that’s how it goes unfortunately.”

Toto Wolff said Mercedes were considering what had happened. “It is the second time we have got taken out, a lot of construction points,” the team principal said.

“To word it in [technical director] James Allison’s words: ‘Do you think it is deliberate or incompetence?’ And that is where it leaves us with a judgment. I am not happy. We had a difficult weekend. Qualifying on pole and then getting taken out on lap one, it puts you on the back foot.”