A British man who fell almost 100 metres to his death from a cliff in Sydney was trying to watch the sunrise with his friends, according to media reports in Australia.

The Sydney Morning Herald reports that the 25-year-old had climbed a fence at the Fairfax Walk lookout at North Head at about 6:45am on Sunday.

Inspector Nigel Taylor was quoted by the newspaper as saying the group walked along the escarpment and sat beside the cliff.

He added: "When they returned to the lookout, the young fella has gone to have a closer look and fallen over the edge."

"To me it's just a completely tragic accident," Police Sergeant Belinda Caddy told Nine News.

"We really feel for his friends that witnessed this, and for his family."

The television channel reported that it is believed two of the man's friends rushed down to the base using ladders used by fishermen - but they discovered he was unresponsive.

His body was later retrieved by a police helicopter.

New South Wales Police said in a statement: "Police from Northern Beaches Local Area Command were called to Scenic Drive at North Head about 6:45am (Sunday 7 December 2014), responding to reports a man had fallen onto rocks."

"Police have been told the man - believed to be aged between 20 and 30 - climbed a fence and walked to the edge of the cliff before falling 90m onto rocks."

"Four people who witnessed the incident are now speaking with investigators."

The man has yet to be formally identified, but a UK Foreign office spokesperson confirmed the death of a British national in Manly.

"We are in touch with local authorities and stand ready to provide consular assistance to the family," a statement said.