US presidential hopeful Donald Trump has been sharply criticised over lewd and sexually charged comments he made about women back in 2005.

The former reality TV star bragged about kissing, groping and trying to have sex with women on a video recording released by The Washington Post and NBC News on Friday.

The celebrity businessman boasted "when you're a star, they let you do it" in a conversation with Billy Bush, then a host of the television show Access Hollywood, as he waited to make a cameo appearance on a soap opera 11 years ago.

The remarks were captured by a live microphone that Trump did not appear to know was recording their conversation.