MANILA, Philippines — The Philippines has started transporting troops and supplies to a disputed island in the South China Sea in preparation for construction work that includes reinforcing and lengthening an airstrip and building a dock, an official said Thursday.

China has protested the visit last month by the Philippine defense and military chiefs to Pag-asa Island, home to Filipino soldiers and fishermen for decades, but which is also claimed by Beijing.

Lt. Gen. Raul del Rosario, head of the Philippine military's Western Command, said troops and initial supplies arrived on Pag-asa island last week. About 1.6 billion pesos ($32 million) has been earmarked for the construction that will also include a fish port, solar power, water desalination plant, refurbishment of housing for soldiers and facilities for marine research and tourists.

China's construction of seven islands nearby in the Spratly archipelago has dwarfed similar activities by rival claimants, including the Philippines, whose frosty relations with Beijing have improved significantly under President Rodrigo Duterte.