Astonishing pictures show how an idyllic tropical bay has turned into a busy sea junction crammed with boats that cause pollution and damage coral.

The picturesque Pi Leh Bay in southern Thailand has soared in popularity with holidaymakers amid the rebound in tourism since pandemic travel restrictions ended.

Clear turquoise waters surrounded by lush greenery and towering limestone cliffs have made it a perfect selfie spot, with trips on wooden longtail motorboats costing around 1,000 Baht (22 GBP). Visitors also go snorkeling and swimming.

But wildlife officials are now banning tourists by limiting the number of boats allowed in the area of national beauty in Krabi province.

Yutthapong Damsrisuk, head of the area called the Hat Noppharat Thara–Mu Ko Phi Phi National Park, said more than 120 boats visit the bay each day, posing safety and pollution concerns as they crowd the shore.

Authorities have vowed to reduce congestion by reducing the number of long-tail boats, limiting zones for water activities, and designating a specific time for boating.

He said: 'This problem requires an urgent solution that must be integrated with relevant sectors, including the private sector and operators in the area.

'The aim is to develop regulations to promote sustainable tourism and ensure it does not negatively impact the environment.

'A pier and small boundary buoys will be installed to facilitate the boats' entry and exit and prevent them from harming coral reefs when dropping anchor.

'For added safety, pillars indicating tide levels will be built as well.'

Thailand's beaches have been rated as some of the most beautiful in the world but mass tourism has had devastating effects on the landscape.

Maya Bay - made world famous by the Hollywood blockbuster The Beach starring Leonardo DiCaprio 23 years ago - suffered a severe destructio of coral reefs and marine ecology.

It was permanently closed for four years but re-opened to tourists on January 1, 2022. It is now spodacillay closed during sensitive months.

Natural Resources and Environment Minister Varawut Silpa-Archa said at the time: 'Maya Bay has been continuously receiving interest from tourists around the world. But this has also caused the natural area to deteriorate, especially the corals.

'After shutting down Maya Bay to revive and restore it, up until the present, it has returned to a good condition.'