MANILA - The Philippines will formalise a chain of direct communication with China in January to avoid "miscalculation and miscommunication" in the disputed South China Sea, an official said on Thursday.

The deal will be signed during President Ferdinand Marcos Jr's state visit to China starting on Jan. 3, foreign affairs assistant secretary Nathaniel Imperial told a news conference.

The Asian neighbours are long-time rivals in the South China Sea, a strategic waterway through which billions of dollars worth of goods pass each year. China claims most of it, despite an international arbitration ruling invalidating that claim in 2016.

Brunei, Malaysia, the Philippines, Taiwan and Vietnam also have overlapping claims to various islands and features.

Marcos, who won an election by a landslide in May, promised to "shift to a higher gear" his country's ties with China, signalling intent to advance his predecessor Rodrigo Duterte's pro-Beijing agenda.

He will meet Chinese President Xi Jinping and discuss bilateral relations, including the South China Sea, Imperial said.

China's embassy in Manila provided no further information on the agreement.

(Reporting by Neil Jerome Morales; Editing by Kanupriya Kapoor)