JAKARTA (AFP) - Indonesian authorities called off their search for two Spanish men Saturday, finding no sign of them one week after their tour boat sank in central Indonesia.

The boat carrying 25 people departed from the island of Lombok near Bali and was headed east toward Komodo Island, a popular tourist destination, when it hit a reef and later sank in stormy weather on August 16.

The 18 other foreign tourists on board, as well as four Indonesian crew and one guide, survived the horrific ordeal.

A team with three rescue boats and three fishing vessels combed the seas around several islands in the area for the final day of the search, to no avail.

"We found no sign of the men at all. There are many fishermen in the area looking out for them, and they will continue to do so, even though we've ended our official search," local search and rescue chief Budiawan, who goes by one name, told AFP.

"Of course we'll come back out if there is any sign of them."

Indonesian authorities were unable to confirm the men's full names, while Spain's foreign ministry identified one as 43-year-old lawyer Victor Garcia Montes from Seville, according to Spanish media reports.

The two men had been with a group of 10 others who swam some five kilometres to the volcanic island of Sangeang. The 10 reached the island, where some drank their own urine and ate leaves until they were rescued the following day.

Another group of 13 people who went out with the vessel's small lifeboat survived. They had to switch between swimming and sitting from more than 40 hours as the boat could hold only seven at a time.

All survivors were treated on the central Indonesian island of Sumbawa.

The foreigners rescued were from New Zealand, Britain, Spain, the Netherlands, Germany, France and Italy.

Komodo is one of several islands that make up the Komodo National Park, a protected area. Its eponymous lizards are a major tourist attraction that grow up to three metres long and have a venomous bite.

Indonesia relies heavily on boats to connect its more than 17,000 islands but has a poor maritime safety record. Boat sinkings involving foreign tourists, however, are rare.