Zaragoza, Spain - The 2008 World Expo on water and sustainable development that ended overnight has been branded a "success," recording 5.65 million visitors since June in the northern Spanish city of Zaragoza, organizers said on Monday.

Organizers had initially said they expected more than 6 million visitors to the Expo.

Visitors included 36 royals, presidents of republics or parliaments, or heads of government, as well as 89 ministers from outside Spain, said Roque Gistau, president of the Expo.

Only 4.6 per cent of the visitors, however, came from outside Spain.

The Expo ended with a fireworks spectacle in the presence of King Juan Carlos and Prime Minister Jose Luis Rodriguez Zapatero on Sunday.

A Water Charter, based on the recommendations of more than 2,000 experts who attended the Expo, urged the international community to make the access to clean water a universal right.

The charter, which also included recommendations on issues such as the equitable management of water, environmental protection and international cooperation on water resources, will be presented to the United Nations.

Zapatero announced the establishment of a climate change research institute in the Expo grounds on the shore of the River Ebro.

More than 100 countries participated in the first world exhibition in Europe since the 2000 Hannover Expo, which brought public and private investments worth more than 3 billion euros (4 billion dollars) to Zaragoza. (dpa)