Lewis Hamilton has expressed frustration with the protracted negotiations regarding his latest contract at Mercedes.

Reigning world champion Hamilton, who moved to the team in 2012 after defecting from rival McLaren, is negotiating the deal himself and had initially expressed hope that the agreement would be sealed in the days following his second-placed finish at the Malaysian Grand Prix.

Confirmation that he has successfully brokered a new contract believed to be worth in excess of £27m ($39.8m) has not been forthcoming, however, with the Briton now forced to turn his attentions to achieving victory in China for the second successive year.

"Obviously at the last race I said it would be done within a week," Hamilton said. "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 quite a pain in the backside to be honest."

Hamilton has qualified on pole for each of the first two races of the 2015 season. While he eased to victory in Australia on the opening weekend, in Sepang he and teammate Nico Rosberg were bested by Sebastian Vettel who perfectly executed a two-stop strategy on his way to a maiden win for Ferrari.

Despite that disappointment, the 30-year-old insists that the lack of closure regarding his contract status is not affecting his on-track performance.

"It will get done eventually," he wrote in his latest column for BBC Sport. "I honestly thought it was very close but, as in all negotiations, things drag on longer than you expect.

"I don't feel like I am in a rush – we're talking about a contract for next season and beyond, so there is plenty of time and it is not affecting my driving at all."

Vettel was obviously delighted to beat Hamilton in Malaysia, yet he has sought to play down suggestions that Ferrari could pose a serious threat to Mercedes' dominance over the course of the entire campaign.

"We did a great job in Malaysia, but we have to be realistic. Mercedes is in a strong position," he said.

The 2015 Chinese Grand Prix takes place at the Shanghai International Circuit on 12 April.