Lewis Hamilton has described Red Bull's threat to quit Formula One as "really odd" and claimed a failure to challenge for the title was not a good enough reason to turn their back on the sport.

Red Bull, who won four consecutive world championships between 2010 and 2013, have said they will end their 11-year spell in Formula One if they cannot find a competitive engine for next season.

Red Bull's relationship with engine supplier Renault will come to an end at the conclusion of the season, with Ferrari now seemingly their only option for 2016 after Mercedes declared themselves out of the running.

In an interview with Red Bull publication Speedweek magazine, the team's outspoken owner Dietrich Mateschitz has set a deadline of late October to decide whether they will continue in Formula One.

But Hamilton, whose Mercedes team can clinch the constructors' championship in Russia on Sunday, is bemused by Red Bull's current state of flux.

"It seems really odd for me, having witnessed Red Bull's success, and then the moment that they don't have success, it is like they have been upset about it, but I have not seen that with any other team," Hamilton said.

"Growing up watching Formula One, when Ferrari lost the championship after having success I don't remember hearing them complaining the next year. You have to keep pushing forward and there is no reason for them to give up.

"They have great drivers, great pedigree, they have had incredible success, and they still have a pretty awesome car.

"All those people who have a job, you're saying you are going to get rid of all those people through something that is not the biggest thing? They can still have success. They just have to work hard at it."

Mercedes will seal back-to-back titles in Sochi if they outscore Ferrari by at least three points.

And Hamilton, who is 48 points ahead of team-mate Nico Rosberg in the drivers' championship with five races left, heaped praise on the team he joined in 2013 after quitting McLaren.

"I think people take for granted what an amazing job a team, a large group of people can do," said Hamilton.

"The one thing I get to see is how on-point every individual in this team has been since I joined.

"It is very easy for a team to have success like they did last year and then drop the ball the next year and get complacent. This team has continued to power through, to keep pushing.

"Every individual that is in this team, they want to do their job to the best of their ability and push the boundaries and be even better, so that we are at a weekend like this where we are fighting for the world championship and able to say we are the best.

"They are able to go home to their kids and say 'I built the best car', 'we are the best team' and that is what everyone wants. So I feel very privileged to have been a part of it."