The top enforcer of former Philippine leader Rodrigo Duterte's deadly war on drugs urged ​president Ferdinand Marcos Jr on Tuesday to not hand him over to the International Criminal Court, but said he ‌was ready to face justice at home.

Fearing arrest and hunkered down in his legislative office for a second day, Senator Ronald dela Rosa said he had faithfully served his country.

The ICC unsealed an arrest warrant on Monday for former police chief dela Rosa, dated November, on suspicion of crimes against humanity, the ​same crimes 81-year-old Duterte is accused of as he awaits trial in The Hague following his arrest last year.

Dela Rosa, better known ​as "Bato", or "rock", has been under the protective custody of the senate since law enforcement agents entered ⁠the building on Monday, when he reappeared in public for the first time since November. He has denied involvement in illegal killings.

"I hope that, as the father of the nation, you will take care of all Filipinos. That is ​the role of government, to care for its people," dela Rosa told reporters when asked what his message was to President Marcos.

"I did everything for the country. I did not enrich myself. I worked faithfully," he said, his eyes welling with tears.

"Mr President, (you) may one day face a situation like this. ​You may also encounter problems, and then you will understand, you will feel what I am feeling right now."

Dela Rosa was Duterte's ​top lieutenant and oversaw a fierce crackdown during which police say more than 6,000 suspected drug dealers were killed in official operations. Thousands of users ‌were also ⁠gunned down in mysterious slumland murders blamed on vigilantes or turf wars.

Police say those killed during operations had resisted arrest and reject activists allegations of systematic murders and cover-ups. On Tuesday, police stood in line behind riot shields outside the Senate, where all committee meetings were cancelled following dramatic scenes a day earlier, when dela Rosa was seen scrambling for the safety of his office ​as agents from the National ​Bureau of Investigation arrived.

At the same time, we will maintain close and constructive communication with the US National police ⁠chief Jose Melencio Nartatez in a statement on Tuesday said no order had been received to make an arrest, but police remain "prepared to act in accordance with lawful directives and established procedures."

The office of ​the president reiterated that the Philippines is no longer a signatory to the ICC's founding treaty ​but can execute ⁠an ICC warrant if requested by Interpol, the same procedure as Duterte's arrest.

Asked by Reuters in a text message how soon an Interpol request could be made, Interior Secretary Jonvic Remulla said: "Only Interpol knows".

The war on drugs was the key platform that swept Duterte to power in ⁠2016 as ​a tough-talking mayor who during televised public speeches promised to kill thousands of ​drug dealers while repeatedly daring the ICC to come after him.

Duterte's defence team at the ICC has said he maintains his innocence and his tough rhetoric was ​designed to instil fear among criminals.