Claire Williams says Nico Rosberg is a "truly" deserving world champion and that she always thought he was "champion material" from when he made his F1 debut with Williams back in 2006.

Rosberg, who sensationally announced his retirement from Formula One with immediate effect on the eve of the FIA prize giving ceremony in Geneva earlier this month, raced for Williams for four years before joining Mercedes in 2010. During that period he only managed two podiums, but she added it was always "pretty clear" he was destined to take the title a fact emphasised by that fine first drive which saw him claim points on his first outing and set the fastest lap.

"I think it was pretty clear. You know when certain drivers come to you and whether they are champion material and he was," she confirmed.

"For him, I think I heard on Sky he had won 23 races the highest number of races without winning a championship, but then you have drivers who win championships on less wins than you have ever heard of or could win one.

"He has done a great job and done everything he's needed to do. For him it probably feels like a long time in the making but he is a truly deserving world champion and I am so pleased for him."

Claire also emphasised how much more pressure was on him, given his family history and the fact his father, Keke, is the 1982 F1 World Champion.

"I remember when he started his career at Williams as I was his press officer at the time and they were doing a shoot with Nelson Piquet and it was nice with Nico there. From that point on he has been absolutely charming and is a great ambassador and a great all-rounder for the sport so I think it is a really well-deserved world championship. I think for him being a son of a former F1 world champion, to achieve what he has and step out of someone's shadow it is not easy," she continued.

"Any child of someone famous who has had those kinds of achievements knows it is not easy to step out of their shadow, Nico has done everything needed to prove he is a worthy individual in his own right and I think that is probably as important as winning a world championship."