As teammates at Mercedes until last year, the pair shared a particularly acrimonious relationship, even though they had been childhood best friends.
"Hamilton and [Valtteri] Bottas are not friends," F1 legend Niki Lauda told La Gazzetta dello Sport.
"But there is no hate, as there was between Lewis and Nico. It was bad for the team but not for them, because it pushed them to go faster."
Now, with Rosberg at the end of his first year of retirement, the German said that he would be happy to be friends with Hamilton again.
"We were very good friends in the past, but it can happen again in the future," he told the German broadcaster ZDF.
"We're not rivals anymore, I'm completely out of it, so I don't see why we could not get along well after some time."
However, Rosberg admits that he has not even had a phone call with Hamilton in 2017, even though they are apartment neighbours in Monaco.
"We're not at that point yet," the 32-year-old admitted.
However, Rosberg hails the new quadruple world champion Hamilton's driving in 2017, and accepts his unique personality and controversial lifestyle choices.
"He does it his way and I have a lot of respect for that, it's a great quality," he said.
"Lots of people don't like what he does and how he is, which is a matter of opinion, but I think it's cool that he goes his own way."
Hamilton goes into the season-ending Abu Dhabi Grand Prix with a 43-point lead over second-placed Sebastian Vettel.