The UN has launched a set of sustainable tourism criteria designed to give businesses a best practice guide on how to promote tourism while minimising environmental effects.

The Global Sustainable Tourism Criteria (GSTC) is based on 4,500 best practice frameworks taken from projects all around the world.

"Tourism is one of the fastest growing industries and a strong contributor to sustainable development and poverty alleviation," said Francesco Frangialli, Secretary-General of the United Nations World Tourism Organization (UNWTO).

"The GSTC initiative will undoubtedly constitute a major reference point for the entire tourism sector and an important step in making sustainability an inherent part of tourism development."

More than 900 million international tourists travelled last year and UNWTO forecasts 1.6 billion tourists by the year 2020.

The criteria focus on four areas: maximising tourism's benefits to local communities, reducing negative effects on cultural heritage, reducing harm to local environments and planning for sustainability.

Many of the guidelines also focus on how operators should ensure that they are adhering to local rules and customs.

The GSTC partnership is developing educational materials and technical tools to guide hotels and tour operators on how to implement the criteria.

The rules will help tourists distinguish genuinely green operators from those firms that are over stating environmental credentials, according to Jeff Glueck, chief marketing officer at travel agency trade association Sabre.

"These criteria will allow true certification of sustainable practices in hotels and resorts as well as other travel suppliers,” he said.

The Rainforest Alliance also welcomed the criteria, arguing that they would allow environmentally-conscious travellers to demand resorts and operators that meet the global standards.

"The Global Sustainable Tourism Criteria that have been developed will shape the minimum requirements that the Sustainable Tourism Stewardship Council will demand from accredited certification programmes and help travellers have the assurance that they are helping, not harming, the environment," said executive director Tensie Whelan.