Defense Secretary Gilbert Teodoro Jr. joined some members of President Ferdinand Marcos Jr's Cabinet who are against a suggestion from ex-President Rodrigo Duterte that Mindanao should secede from the Philippines.

''The mandate of the Department of National Defense is to secure the sovereignty of the State and integrity of the national territory as enshrined in the Constitution. We will strictly enforce this mandate whether externally or internally,'' said Teodoro in a statement on Monday.

The Department of Justice, in a statement, declared that it “opposes calls for the secession of Mindanao and stands firmly against any attempts to undermine the unity and territorial integrity of the Philippines, as enshrined in the Constitution.”

“Secession is regarded as contrary to the principles of our democratic society, as stated in Article II, Section 2 of the Constitution,” the DOJ said.

Last week, Duterte said '' a regrouping of the political works'' remains in the works which could lead in a drive to separate Mindanao from the Philippines.

Two former cabinet secretaries who served under Duterte strongly opposed his calls to separate Mindanao from the rest of the country, warning the government will not hesitate to use its authority and forces to stop any attempt to dismember the Republic.

In a statement, Presidential Adviser on Peace, Reconciliation and Unity Secretary Carlito Galvez urged the Filipino people to turn down any call or movement aiming to destabilize the Philippines, especially calls to separate Mindanao from the rest of the Philippines.

Galvez, who was Duterte’s Armed Forces of the Philippines (AFP) chief of staff, said: “As Filipinos, let us therefore continue supporting the Marcos administration’s peace, reconciliation and unity agenda. The dividends of peace are upon us and are now being felt by everyone.”

“The members of these former revolutionary groups are now playing an active part in nation-building. They are helping the national government promote genuine peace and sustainable development in the Bangsamoro through inclusive, people-centered moral governance,” he added.

Galvez said the Philippines cannot afford to go back to the old notion about Mindanao as it is has now become a symbol of hope, mutual understanding and solidarity, and “a shining example that good things come to those who choose the path of peace.”

National Security Adviser Secretary Eduardo Ano, who served as Duterte’s Interior secretary, also turned down calls to separate Mindanao from the rest of the Philippines.

In a separate statement, Ano said the call for division “only serves to undermine” the collective efforts of the Filipino people towards progress and prosperity.

“In light of recent calls to separate Mindanao from the rest of the Philippines, we underscore the importance of national unity, security and stability,” Ano said. DMS