A British tourist has gone missing from a popular beach in Australia alongside his French companion.

Police have launched a search for 20-year-old Englishman Hugo Palmer and his friend Erwan Ferrieux, also 20, after items belonging to the pair were discovered at Shelly Beach, on the New South Wales coast between Sydney and Brisbane.

Walkers found their belongings at about 6.30am on Monday, and police later discovered their rental car in the beach's car park with a number of personal items, including travel documents, inside.

New South Wales Police said they had carried out a water and ground search, but there had not yet been any sign of the pair.

Sources told local news outlets the backpackers are believed to have gone swimming, and Sydney locals said the beach was known for snorkeling and scuba diving due to the fact the water was usually calm there.

But Inspector Michael Aldridge told the Port Macquarie News surf conditions had been "terrible" over the past few days. He believes the missing pair had arrived in the area on Sunday morning, just hours before vanishing.

Inspector Aldridge said: "We believe from information provided so far that the items may have been there since Sunday evening as well.