Lewis Hamilton has said that contract negotiations with Mercedes, which he's handling himself, are still ongoing, due - in part - to the size of the contra Lewis Hamilton has said that contract negotiations with Mercedes, which he's handling himself, are still ongoing, due - in part - to the size of the contra

Lewis Hamilton has admitted he doesn’t know when his new contract with Mercedes will be signed, describing the unfolding saga as “a pain in the backside”.

Hamilton’s current deal with the Silver Arrows expires at the end of the season and the 30-year-old, who represented himself in negotiations with the team’s hierarchy over the winter, told Sky Sports two weeks ago that a deal had been agreed in principle.

But ahead of this weekend’s Chinese GP, an exasperated-sounding Hamilton admitted that the new deal remains unsigned.

“I think it is unlikely,” Hamilton told Sky Sports News HQ when asked if his contract would be signed this week.

“Obviously at the last race I said it would be done within a week, this is my first time negotiating myself and you don’t know how many times I’ve had to read about 80 pages – it is so much reading and it is all in lawyer jargon. So it has been a quite a pain in the backside to be honest.”

After the Malaysia GP two weeks ago, Hamilton scoffed at the suggestion he was considering a switch to Ferrari following the Scuderia’s sudden re-emergence as a major force in the sport and assured reporters that the new deal was "99.6 per cent" done.

However, even if he is not joining them, Hamilton is hoping be battling the Scuderia and Sebastian Vettel at the front of the pack in Shanghai this weekend.

“This is a race where it is much cooler than the last race," he added.

"In previous years Ferrari have always struggled to get temperature up in their tyres, but they have done a good job in previous years here.

"I think it will be really interesting, but I am up for a race – I hope we have a race with these guys because they are just as quick as us on the straights and they had amazing pace in the last race. So hopefully for the fans you get to see some battling between myself and Sebastian.”

Hamilton, who currently leads the world championship from Ferrari's Vettel and Mercedes team-mate Nico Rosberg, won his second title last year after joining the Silver Arrows from McLaren in 2012.