Israel, Jordan and the Palestinian Authority learned Friday that the Dead Sea had not been voted as one of the New 7 Wonders of Nature.

For Pini Shani, head of overseas development at the Israeli tourism ministry, it was a missed opportunity, especially considering the $2.1 million (1.5 mln euros) they pumped into a high-profile campaign.

Israel's Tourism Minister Stas Misezhnikov put a brave face on it, calling it the campaign "a true victory."

"Thanks to the impressive campaign led by the Ministry of Tourism over the last two years, hundreds of millions of people worldwide have now been exposed to the Dead Sea and Israel," he said in a statement.

"This is a true victory for Israels image abroad, the fruits of which we will see in the next few years in the investment in the rehabilitation and development of the Dead Sea."

Even had it been included as one of the new wonders, Israeli, Palestinian and Jordanian celebrations would have been held very much apart, a reflection of their separate campaigns to promote this unique inland lake.

The Dead Sea lies at the lowest point on the Earth's surface, 423 metres (1,387 feet) below sea level.

One of the saltiest bodies of water in the world, it was among the 28 finalists in a massive Swiss-run Internet campaign to chose the New 7 Wonders of Nature.

With its eastern shores in Jordan, its western shores in Israel and some 40 kilometres of its northwestern corner in the Palestinian territories, it had backing from all three governments.

But each ran their own campaign.

"There was no practical cooperation between the states -- we tried to initiate it a number of times and received negative answers," said Pini Shani, head of overseas development at the Israeli tourism ministry.

Israel invested some $2.1 million (1.5 mln euros) in a global PR campaign, most of it online, said Shani. Prime Minister Benjamin Netanyahu and other high profile Israelis, such as supermodel Bar Refaeli, helped back the drive.

"The competition has high economic value, by participating in it, and certainly if we win it," Shani told AFP.

And even without the win, with organisers anticipating that up to a billion people would vote in the campaign, it was bound to give the region "massive" exposure, he said.

The Dead Sea is often described as the world's largest natural spa, thanks to a combination of its silky, sulphur-infused waters and mineral-rich black mud. And along with the historical sites along its shores, it is a huge draw for tourism.

Approximately half of the 3.45 million tourists who visited Israel in 2010 went to the Dead Sea, tourism ministry data show, making it the third most visited location after Jerusalem and Tel Aviv.

On the western shores, all of the Dead Sea's 67-kilometre (42-mile) coastline is under Israeli control, although nearly two thirds of it -- 40 km or 25 miles -- falls within the occupied West Bank.

Palestinian tourism minister Khoulud Daibes recently said they had decided to join in the competition "to confirm our right and ownership of part of the Dead Sea and to prevent Israel having an opportunity to claim full control."

In Jordan, tourism ministry head Issa Qammou said they had launched their own global campaign a few months ago. He did not comment on the issue of regional coordination.

But the Dead Sea is rapidly drying up, largely because the supply of fresh water that once flowed in from the Jordan River has been cut to less than 10 percent of its original flow due to heavy agricultural use by Israel and Jordan.

And Israel and Jordan's use of evaporation ponds as a way to extract minerals from its briny waters has only exacerbated the problem.

According to World Bank data published in 2010, the lake's surface area has been reduced by one third since the 1960s and in 2007, it measured just 637 square kilometres (246 sq miles) compared to 950 (366 sq miles) some four decades earlier.

And the water level continues to drop at a rate of approximately one metre (3.3 feet) per year.

Some believe that winning would raise global awareness about the dire problems facing the sea, but for Shani the main reason behind the campaign was to promote tourism.

"Tourism helps the entire region -- it is an element that transcends borders," he said.

The fact there was no regional cooperation over the campaign was a missed opportunity, he said.

"If we could have been able to present the world with a picture of Jordan and Israel jointly promoting the Dead Sea, that would no doubt have carried a very positive image, and in general on tourism."

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