China is aiming to make the free trade port system and operational mode of Hainan "more mature" by 2035, according to a document unveiled Saturday.

A free trade port system will be "basically established" in Hainan by 2025, according to the guidelines on supporting Hainan's efforts to deepen reform and opening up jointly released by the Central Committee of the Communist Party of China (CPC) and the State Council.

China will also set up an investment fund to support Hainan's development of a free trade port.

A free trade port is the world's most open form of economic zone, which has brought prosperity to places like Singapore and Hong Kong thanks to its broad-based preferential policies on trade and investment.

Chinese President Xi Jinping Friday announced a decision by the CPC Central Committee to support building Hainan into a pilot free trade zone and gradually and steadily into a free trade port with Chinese characteristics.

China welcomes investors worldwide to invest and start business in Hainan and participate in the building of a free trade port there, Xi said at a celebration marking the 30th anniversary of the establishment of Hainan Province and the Hainan Special Economic Zone.

China will support the "all-round participation" of foreign firms in the development of the Hainan free trade port, and multinational companies are encouraged to set up international and regional headquarters there, according to the document.