Christian Horner has confirmed that he held talks with Fernando Alonso earlier this season about a possible move to Red Bull.

The story first came to light in May, when Helmut Marko revealed that Red Bull was one of several teams the Spaniard had approached before committing his future to Aston Martin.

"There have been conversations," the Austrian told Formel1.de. "But as I have mentioned before, a harmonious work environment is very important to Max and I think that probably would not have been the case with Alonso.

"I think it would be very difficult for a team," he admitted. "Alonso would be the oldest world champion on the team, Max the youngest, and they are generations apart. I don't think Alonso does sim racing or gets into a simulator on a plane right after a grand prix. They are two opposite personalities, both very good drivers and also personalities. Neither of them are very modest. And it would be very, very difficult for a team to take that in a positive direction."

Speaking in Mexico, Horner confirmed that talks did take place, adding that it wasn't the first time the Spaniard had been linked with the Austrian outfit.

"At that time Sergio's contract hadn't been extended," explained Horner, "so as Fernando is a seasoned operator, he always wants to know all of his options.

"Between him and his manager or advisor, Flavio, they're always testing the market. It just shows how hungry and competitive he is, and he's still delivering at 43 years of age.

"He's still in great shape, and it just shows that age is just a number, so yeah, he's still a very capable pre-driver, given the tools, I'm sure he'll be at the front.

"He's a formidable competitor," he continued, "at the end of his McLaren stint, I remember going to Madrid and pushing to get him in the car.

"We wanted to do a two-year deal, and he was only prepared to sign for one year, and we were convinced he had a Ferrari contract in his back pocket at that point," added the Briton. "So we didn't get to a deal.

"Had he come to us in 2009, maybe things could have looked slightly differently. Even halfway through the 2009 season, he was convinced if he got in our car, he could still win the championship that year.

"It was at that point, we had a conversation, I remember meeting with him, and with Adrian, in the back of a hire car at Spa Airport, and I think that was around 2011, '11 or '12, about again coming across with a Ferrari, maybe even as early as the beginning of this year.

"It's incredible the longevity that he's had," he said of the Spaniard who starts his 400th grand prix this weekend, "the competitiveness that he has, the talent that he has, the ability he has, two World Championships, he should have won more than that."

Check out our Saturday gallery from Mexico City here.