Michael Jackson's doctor has spoken for the first time since the singer's death on June 25.

Dr Conrad Murray, who is at the centre of the police investigation, was with the singer when he suffered a cardiac arrest at his home in Holmby Hills, Los Angeles.

In a video message on YouTube, Dr Murray insisted that he had “told the truth and I have faith the truth will prevail”.

Jackson's personal physician said the video, which was recorded last week in Houston, was his way of thanking his supporters for their messages.

“Your messages give me strength and courage and keep me going,” he said.

“They mean the world to me."

Dr Murray added: "Because of all that is going on, I am afraid to return phone calls or use my e-mail, which, as you know, is not normal for me.”