Nico Rosberg: Retirement not a difficult decision

Gow: A brave decision from Rosberg (1:42)

Jennie Gow says Nico Rosberg has made a brave decision in retiring from Formula One so soon after his title win. (1:42)

VIENNA, Austria -- Nico Rosberg says his decision to retire as world champion was not a difficult one, adding that the moment felt right.

After winning the title on Sunday night, Rosberg announced his retirement on Friday ahead of the FIA prize giving gala in Vienna. The decision came as a complete surprise to the F1 media and his team Mercedes was only informed earlier this week, but Rosberg said he knew the timing was right.

"For me it's not that difficult because it just feels right," he said. "The only thing that makes it difficult is that I know that I am putting my racing family [Mercedes] into a difficult situation - that's the hardest part for me."

Rosberg said he started contemplating retirement after his final victory earlier this year in Japan. The win at the famous Suzuka circuit with four rounds remaining meant the title was his to lose, with three second places and third enough to secure the championship regardless of what teammate and title rival Hamilton achieved.

"It was after Suzuka because in Suzuka it became my title to lose," he said. "That's when the pressure really started and I started to think about this, that if I do achieve my childhood dream then it would be great to end there. "For sure, I put absolutely everything into it. It was very, very tough and Lewis is an amazing driver and one of the best out there and to beat him is extremely tough. The last four races, but especially the last race were unbelievable -- crazy stuff."

After achieving his childhood dream, Rosberg said he did not want to put his family through that level of stress again. "It's very simple, I've achieved what I set out to do. It's unbelievable how clear it was for me, when I was six years old -- you have seen the video I shared on Facebook -- I remember that was my dream. I set out to win the world championship and that was probably inspired by my dad.

"Of course then it was more of a childhood thing and in later years it became more and more serious, and going for that, I am just so happy [to achieve it]. And at the same time, as I explained, it was a very tough year and I don't want to do that again."