PHILIPPINE President Rodrigo R. Duterte on Monday night barred his Cabinet from talking in public about the country’s sea dispute with China, which some of his ministers had rebuked for its actions in the disputed waterway.

“If we have to talk, we talk among ourselves,” he said in a televised speech. Only his spokesman can talk about the issue publicly, he added.

Foreign Affairs Secretary Teodoro Locsin, Jr. this month minced no words in telling the Chinese to get out of Philippine waters in the South China Sea, cussing at its neighbor for failing to reciprocate its goodwill.

The presidential palace later distanced itself from Mr. Locsin. Presidential spokesman Herminio L. Roque, Jr. said Mr. Duterte is against the use of profanities in the field of diplomacy.

Mr. Locsin later apologized to his Chinese counterpart, Foreign Minister Wang Yi, after his expletive-laden tweet.

Defense Secretary Delfin N. Lorenzana had also told Chinese ships in the disputed sea to leave.

“Only the secretary of Foreign Affairs and myself can speak on the issue now,” Mr. Roque told a televised news briefing on Tuesday.

He said a Philippine task force on border patrols had also been barred from commenting on the issue.

The task force earlier said 287 Chinese ships were still in Philippine waters, many of them spotted near artificial islands built by China, while some were near islands occupied by Manila, based on patrols made on May 9.

Two Houbei class missile warships were also near Mischief Reef, while two Vietnamese logistics ships and a VN Coast Guard vessel were at Grierson Reef, it said.

Thirty-four Chinese ships also remained at Whitsun Reef, which the Philippines also claims.

The government would continue to defend its sovereign rights and jurisdiction over the “West Philippine Sea,” the task force said, referring to areas of the waterway within the country’s exclusive economic zone.

“Reports of the National Task Force are forwarded to the Department of Foreign Affairs and they would determine if they will file a diplomatic protest,” Mr. Roque said.

He said the Philippines would continue to “patrol relevant areas to assert what is ours.” “Our principled position and stand on the West Philippine Sea remains. Our vessels will continue.”

Meanwhile, Senate President Vicente C. Sotto III urged Malacañang to consider an “alternative response” by looking at the feasibility of starting oil exploration studies within the country’s exclusive economic zone to assert its jurisdiction in the area. 

“The public discourse over the West Philippine Sea boils down to one thing: While the United Nations ruled in our favor, the ruling cannot be put in force because of the absence of an international body that would enforce it,” he said in a statement. “But we can use this arbitral victory to our advantage.”

He said the Department of Energy could propose to conduct exploration activities in the contested areas and open initiatives to private investors and even other countries under a 60-40 joint agreement.

China cannot stop the Philippines from exploring natural and mineral resources within its exclusive economic zone, Mr. Sotto said. If China is interested, it can be a joint partner, he added.

A United Nations arbitration panel in 2016 favored the Philippines and rejected China’s claim to more than 80% of the disputed waterway based on a 1940s map.

The Philippines under President Benigno S.C. Aquino III filed the lawsuit that critics said Mr. Duterte had failed to pursue.

Aside from the Philippines and China, Brunei, Malaysia, Vietnam and Taiwan also claim parts of the waterway.

Meanwhile, Senator Panfilo M. Lacson agreed with former Senate President Juan F. Ponce-Enrile that the government should continue diplomatic talks with China.

“But neither should we disregard other options available, not only to finally resolve the West Philippine Sea issue but to provide the balance of power in the Indo-Pacific region,” he said in a statement.

Mr. Lacson said the Philippines should build stronger alliances with powerful countries.

Mr. Enrile advised Mr. Duterte during a taped meeting on Monday to continue its friendly approach with China.

Senator Ralph G. Recto said the Philippines should work with its allies including the United States and others “who share similar interests and values of a rule-based order.”

“It is in the interest of most nations to uphold our UNCLOS victory,” he said, referring to the United Nations Convention on the Law of the Sea. “We can maintain trade relations with China at the same time.” — Kyle Aristophere T. Atienza and Vann Marlo M. Villegas