Hamilton will be 36 when his megabucks deal, which makes him the highest paid driver in the history of Formula One, expires.
Although he now trails rival Sebastian Vettel by 15 points in the Drivers World Championship, Hamilton insists the his team are "more hungry than ever" and "eager to win", adding that his "competitive passion is shared by each member of the group".
Red Bull's Ricciardo is yet to commit his future to the F1 team.
"I'm very confident that Mercedes is the right place to be over the coming years", Hamilton said.
The championship leader, racing on home soil for the first time in two years, painted a gloomy picture of the future, however.
Lewis Hamilton is hoping to get revenge on Sebastian Vettel
Pushed on whether the team were Ferrari, he replied: "You can make whatever assumption you want".
I think Charles, one way or the other, will have a great career, he's a great guy, he's fast, he's got everything.
The team put a photo on social media of a contract waiting to be signed, alongside the word '#Announce'. We have had our ups and downs as every relationship does, but it has been one of a lot of growth, and I really appreciate Toto being so patient with me. I said from day one, "look I'm not talking to anyone else, I'm not investigating to see what other options there are, I'm not playing you against anyone else".
"Maybe the nation is a little bit full or exhausted of racing, I don't know", ventured Renault's Nico Hulkenberg, now one of just two German drivers on the grid but still without a podium finish to his credit in 145 starts.
Confirmation of his new contract could even come as early as this weekend's German Grand Prix.
"I wasn't expecting to feel as excited as I am now in signing this extension. For me it is clear where I am next year but I think both of them would suit into the team". "This is probably the last time for a while as far as I understand, which would be a shame - to lose one of the classic races".