Lewis Hamilton says heavy partying and a lack of sleep has taken its toll in a week in which he was involved in a mysterious car crash.

Hamilton, who revealed via his Instagram account that he hit a stationary car in his home town of Monaco, initially refused to field questions on the incident in his pre-race media briefing ahead of the Brazilian Grand Prix.

A Mercedes spokesperson said the Briton, who has arrived in Sao Paulo a day later than planned, was “not going to expand and elaborate on the events of this week’’.

But Hamilton, who was believed to be driving his limited edition Pagani Zonda supercar – worth €2.25 million – at the time of the incident, later admitted to feeling “run down”.

Hamilton claimed the accident happened on Monday night, but it is understood it occurred at approximately 3.30am on Tuesday morning – the same day he was due to fly to Brazil.

“It was a result of heavy partying and not much rest for a week and a half,” said Hamilton, when asked about the crash and his overall health.

“I am a bit run down. I have been non-stop and trying to fit training in at the same time and not getting a lot of sleep.”

Hamilton, who threw a surprise 60th birthday party for his mother Carmen in London on Saturday, has also been battling a fever.

“I don’t feel as bad as I look but I honestly feel a lot better,” he added. “The last two days I have slept pretty much all day.

“I couldn’t believe how much I slept. I slept on the flight here, too. I was nervous that I was not going to sleep on the flight. I slept all day yesterday.

“I usually sleep four or five hours but when you are training you need more than that. I am generally a really energetic person but that week after Mexico and the party we drank a lot and I was really feeling it.”

Hamilton was set to fly to Brazil on Tuesday night ahead of the penultimate race of the season, but the 30-year-old delayed his journey by 24 hours.

He subsequently missed a sponsors’ event in Sao Paulo with local reporters claiming he may be absent from Sunday’s race.

“I never considered not coming,” Hamilton, who is yet to win in Brazil, added. “I have never ever not considered coming to a race throughout my whole life. In 22 years, I have never not been at a race.”

Hamilton chose to break the news of his car crash via his social media account on Thursday, but the specifics of the event remain unclear.

Hamilton wrote: “Whilst ultimately, it is nobody’s business, there are people knowing my position that will try to take advantage of the situation and make a quick buck. No problem.

“Nobody was hurt, which is the most important thing. But the car was obviously damaged and I made very light contact with a stationary vehicle.

“Talking with the team and my doctor, we decided together that it was best for me to rest at home and leave a day later.

“I am informing you because I feel we all must take responsibility for our actions. Mistakes happen to us all but what’s important is that we learn from them and grow.’’