Malacanang said on Monday foreign investors should instead be "happy" with what the Duterte administration has been doing regarding the issue with the country's two major water concessionaires.

In a press briefing, Presidential Spokesperson Salvador Panelo said this should serve as a warning to investors not to enter into contracts that would violate the Philippine Constitution.

"They should be happy because the government won't allow these kinds of contracts which destroy the interest of the Filipinos," he said.

"So, they are already forewarned that the contracts, which violate the law, the Constitution, and the general welfare of the Filipinos, are not allowed. So, they will be cautious, when they invest, they already knew the right terms which won't destroy their business," explained Panelo, also chief presidential legal counsel.

Some Japanese investors, such as Marubeni Corp. and Mitsubishi Corp., have stakes on water concessionaires Maynilad Water Services, Inc. and Manila Water Company, Inc., respectively.

Since Duterte threatened to dishonor the concession agreements by the government with the two companies due to alleged "onerous" and disadvantageous" provisions, the shares of the water companies and their affiliates at the stock market have been affected.

Panelo, quoting Duterte, said that there were not even contracts to speak of between the government and Manila Water and Maynilad as their concession agreements were "void ab initio."

"It's null and void at its inception. So, you cannot even say that there is a contract. What contract? What we have entered into was null and void, that's why we will not respect it from the very beginning," he said.

Panelo earlier said Duterte would make an announcement Monday regarding the issue of the water concessions.

Duterte is set to preside a Cabinet meeting on Monday. Celerina Monte/DMS