A rescue is underway for an injured rock-climber stranded on a Blue Mountains cliff for more than 20 hours.

The man, believed to be in his 50s, suffered multiple fractures when he fell halfway down a 150-metre cliff around 4 pm yesterday.

The injured man and one of his companions were sheltered in a cave on the cliff face with rescue personnel overnight.

It is expected he will be lowered to the valley floor before a helicopter extracts him.

9News reporter Zara James told Deborah Knight the men are understood to be experienced climbers.

“They’re saying it could be at least another two hours before they’re even able to get him to the top.

“There are changing conditions here at the moment… you wouldn’t be able to get a helicopter up here right now.”

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