It was a clearly hesitant Lewis Hamilton that shook the outstretched hand of Formula One title rival Nico Rosberg to signal the start of this weekend's countdown towards either championship ecstasy or agony.

Organised by the FIA ahead of the final drivers' press conference of the year, the Mercedes team-mates were asked to take centre stage for a minute for the assembled photographers.

Rosberg was the first to extend his right hand, with Hamilton pausing for a few moments before reaching out in reply, gripping tightly.

As olive branches go, with Rosberg appearing to smile warmly but with Hamilton playing it more straight-faced, it was an uneasy truce ahead of battle commencing this weekend in Abu Dhabi.

At stake is the 65th F1 world title, motorsport's most-glittering prize, with only Hamilton and Rosberg in the running.

Holding a 17-point lead, Hamilton has the advantage, insisting that "in terms of the pressure, I don't feel any".

Hamilton added: "I've had plenty of experience through my racing career - 15 odd years I would say, actually it might be 20 years of racing - to be prepared for today. There's no special recipe for it."

Of the two, though, it was Rosberg who came across as the more relaxed, joining in with, and laughing at, the banter that unfolded at times on a front row occupied by Fernando Alonso, Sebastian Vettel and Jenson Button.

Arguably there is less pressure on Rosberg, even though the double points on offer for this race aid his cause more than would ordinarily have been the case when it comes to the various permutations.

First and foremost, the 29-year-old German has to finish ahead of Hamilton, and beyond that he needs a helping hand.

A Rosberg victory, for instance, means Hamilton has to finish third or worse, hard enough when you consider Mercedes have finished the last six races one-two.

Assessing his chances, Rosberg said: "I wouldn't use the word pressure, but it's going to be intense, a great battle.

"I look forward to it as it's what I've been working towards for a while now, for this sort of chance, this last race here.

"Lewis is a great competitor and opponent, and it will hopefully be a great end to the season.

"Of course, I'm here to try and win the race, and then I need a bit of help from Lewis that he doesn't finish second. That's it. So I'm hoping Lewis can come up with something."

The line of questioning soon turned towards whether the duo can keep it clean given certain incidents this season, and considering other last-race championship scraps where underhand tactics have been used.

Rosberg's questionable manoeuvre in qualifying in Monaco and then his decision not to take avoiding action ahead of a collision with Hamilton in Spa have been undoubted talking points this year.

Asked whether it would be a totally clean fight, Hamilton replied: "Yeah, I don't really know what else to say. That's how it's been.

"You have to go into the weekends believing that's going to be the case."

Pushed as to whether any conversations between the duo would be necessary ahead of the race, Hamilton initially issued a stern "no".

Suggested to the 29-year-old it was either not required or they already had an understanding, Hamilton added: "We don't need to.

"It's already been discussed at the beginning of the season and several times through the season, and particularly after Spa.

"There's no reason to revisit it. We're not children, we should know what is wrong and what is right."

Asked for his thoughts, Rosberg made clear it is down to Hamilton to stay on the straight and narrow.

Given Hamilton has the lead it is he who could instigate an incident and potentially take both himself and Rosberg out of the race and so win the title, as has happened previously in F1.

But a tetchy Rosberg pointedly said: "Lewis can do something to keep it clean which is drive cleanly himself. It's not like he can't do anything."

In an instant the handshake at the start had soon been forgotten, with the gloves firmly off between the championship-chasing pair.