MANILA – The Palace on Friday stressed that the investment pledges bagged by the Philippines from several Chinese firms during President Rodrigo Duterte’s state visit to China are not yet set in stone.

The government was criticized by the opposition after it was learned that a Chinese state-owned company said to have been involved in Beijing's island-building in the South China Sea signed a deal to construct islands in the Philippines.

CCCC Dredging will create four artificial islands totaling 208 hectares of reclaimed land in Davao, the port city on the southern island of Mindanao where Duterte was mayor, according to Beijing Youth Daily.

Fending off criticism that the move is an affront to Phiilppine sovereignty, Presidential Spokesperson Ernesto Abella said the deals are not yet final and will still go through the regular process.

“Those MOUs (memorandum of understanding) are, in my understanding, they can submit feasibility studies but still subject to public bidding. These are not necessarily contracts or commitments to contracts,” Abella said in a news conference.

The deal with the Philippines' Mega Harbour Port and Development was one of several inked as Duterte paid a state visit to China last week, when Beijing offered $9 billion in soft loans for development projects.

Duterte has sought to restore his country's ties with China, brought low by a territorial dispute over the South China Sea, and during his trip announced his "separation" from longstanding Philippine ally the United States.

In a case brought by his predecessor Benigno Aquino, the Philippines won a resounding victory at an international tribunal earlier this year over Beijing's extensive claims, infuriating the Asian giant.

China has built up artificial islands, some with airstrips, capable of hosting military facilities.

Dredging vessels owned by CCCC Dredging subsidiary CCCC Tianjin Dredging were spotted working in the Spratly archipelago disputed by Manila, according to an analysis of satellite imagery from IHS Jane’s Intelligence Review.

In the Davao project, a perimeter of sand bags will be dropped into the sea, and sand pumped into the space, displacing water until an island is formed, the Monday report explained.

CCCC Dredging, a subsidiary of the China Communications Construction Company (CCCC), is the world's largest by dredging capacity, according to the official website of the Chinese shipping industry.

Aside from CCCC Dreding, China Road and Bridge Corp. also made an investment pledge to the Philippines.

China Road and Bridge Corp., apparently, was was debarred by the World Bank for eight years, beginning January 12, 2009, along with six other firms and one individual. - with Agence France-Presse