A policeman has spent a cold night helping a teenage bush walker who became lost in wild terrain near Western Australia’s highest peak.

The search for the 18-year-old began mid-afternoon on Saturday after an emergency beacon was activated in the Stirling Ranges National Park.

The teen was bushwalking near Bluff Knoll, but become disoriented and did not have any food or water with him.

A rescue helicopter was sent, but was forced to return to Perth because of foul weather, so a police helicopter was sent out and a tactical flight officer was lowered to the ground to make his way to the lost youth.

It was too risky to conduct an emergency winch rescue, so the police helicopter headed to Albany, and the officer spent the night with the teen to ensure he was all right.

The officer reported some rain, but said the two of them were managing well.

Ground-based rescue teams returned to the area on Sunday morning and are expected to take up to three hours to reach the pair.