A week-long official search for a Wagina man in the Western Solomon Islands, who has been missing at sea for a week, has been called off.

The search covered about 700 square kilometers of ocean, and was done with six vessels and a RAMSI aircraft.

Solo Ngatonga went missing on Monday week after a night drinking at Nukumaroro village in Choiseul Province.

He had chosen to travel back to Hay Cook Island in the early hours by boat, but has not been seen or heard from since.

The director of marine search and rescue, Edward Tokuru, says Mr Ngatonga is now presumed drowned, after his boat washed ashore over the weekend on Kilokaka village, in neighboring Isabel Province.

"We believe that he attempted to swim ashore, because the petrol tank that was attached to the outboard motor was also missing with the person and his clothes, his trousers belt and shoes were all on that boat."

Edward Tokuru says they conducted the search despite still waiting for this year's budget allocation.