The move aims to protect the famous site of UNESCO heritage Ha Long Bay after recent studies found that the islet is facing serious erosion and may collapse.
Speaking to local media, deputy director of Quang Ninh Provincial Transport Department, Vu Van Kinh, said that they're going to arrange styrofoam buoys around Trong Mai to keep boats at least 70 metres from the islet.
"We'll co-operate with the Ha Long Bay Management Board and concerned agencies to ask tourist boats to follow the new regulations," Kinh said.
Lying five kilometres from Tuan Chau International Port, the Trong Mai Islet, resembling a pair of a rooster (trong) and a hen (mai) facing each other, is famous for its unique shape among thousands of islets in Ha Long Bay.
A recent study carried out by the Institute of Geosciences and Mineral Resources disclosed that the Trong Mai Islet is at peril of sliding and toppling.
A report from the institute showed that the islet had many cracks, causing the rocks to break and shatter, increasing the risk of collapse. As many as 40 blocks within the islet might fall.
"Human activity, including illegal fishing and unregulated tourism, has further hastened the erosion and landslide processes affecting Trong Mai Islet," the report said.