Fernando Alonso says there was never any possibility of moving to Mercedes for 2017 even though the world champions contacted him after Nico Rosberg's retirement last year.

Rosberg's decision to quit five days after winning the 2016 championship left Mercedes frantically searching for a replacement, with Alonso emerging as an early favourite. It raised the prospect of Alonso rekindling his infamous 2007 partnership with Lewis Hamilton at McLaren, though the Spaniard soon ruled himself out of a move.

Speaking at the launch of McLaren's new car, Alonso said he is fully committed to the third and final year of his deal.

"I think we all had conversations," Alonso said when asked about whether Mercedes had contacted him. "So let's say that Mercedes... after the shock of Rosberg, they had to check of everyone, which is understandable. It was nothing really strange or deep into the conversation, or the possibilities, it was just a round check they did with everyone.

"For them it was to hear my situation and my situation was very clear -- I have this year at McLaren-Honda, I am happy here and there was no point to talk any more or any possibility [of moving]."

Alonso's future beyond the expiry of his McLaren contract at the end of this season is uncertain. The two-time world champion has previously said his desire to stay in the sport will be dictated by how enjoyable he finds the 2017 cars.

However, the Spaniard admits the pecking order under F1's new regulations will also help him decide what he wants to do beyond 2017 -- though he does not expect to start thinking about it before the summer break in August.

After being probed about whether he would categorically rule out a move to Mercedes -- who have signed Valtteri Bottas to a one-year deal -- in future, Alonso said: "I think for the future we will see. Until August, September, there is no point to talk about anything because I will be fully concentrated on this year's championship and we need to see which of the cars and the teams will be competitive with the new rules. Maybe we find out a new team dominates Formula One with these new cars, so that's the first thing.

"So when Rosberg retired there were a couple of days where I had some conversations, some phone calls arrived to me, but I was not willing to discuss anything because I was happy at McLaren.

"I think McLaren-Honda, along with Ferrari, are the two most prestigious teams. Right now they are not winning, that is true, but we saw even today, it's a coincidence but the two best teams in the history of Formula One release their cars on the same day in a proper way. So we need to see how these new cars perform and who is dominating the sport with the new regulations, if it's still Mercedes or not for the future."