Rosberg and Hamilton crashed into each other at the start of the Barcelona race to leave Mercedes point-less in a grand prix for the first time since the 2012 season.

The championship leader, however, says he has moved on already, and insists nothing will change in his relationship with Hamilton.

"It's always very hard work because we are fighting for the championship for the last three years," said Rosberg at the end of testing in Barcelona.

"But, on the other hand, we're also running for the team at the same time, so it's hard work but also nice, because we push each other.

"Obviously it didn't go well for us on Sunday, but our relationship remains as before.

"I don't even think about it anymore, for me it's way in the past and it surprises me that people are talking about it. But I understand it. For me, though, it's over."

He added: "In the end we're here to fight for the win, to fight against each other. That's what the team wants too, that's what brings excitement within the team and, obviously, it didn't go well last Sunday.

"But that's past, so let's look ahead – I don't think about it anymore and I was focussed on the test, on doing well today, to understand everything and I've learned quite a few things today."

Ferrari rumours

Italian media speculated this week that Ferrari could be flirting with Rosberg as a possible replacement for Kimi Raikkonen for next year.

The German's contract expires at the end of the current season, and although he said he is happy where he is, he suggested he is open to a future elsewhere.

"I'm happy at Mercedes, but let's see what the future brings," he said.