Senate President Aquilino "Koko" Pimentel on Friday slammed the European Parliament's call for the "immediate release" of Senator Leila de Lima.
De Lima is under detention for her alleged involvement in the drug trade in the national penitentiary when she was justice secretary.
"The EU Parliament has crossed the line... Parliaments are free to air their sentiments on various issues... but they should refrain from interference in internal affairs by commenting on and worse, demanding the reversal of certain actions taken by sovereign nations," Pimentel said in a statement.
Prior to De Lima's arrest and detention, the Senate majority ousted her as justice committee chief after she held a public hearing with confessed hitman, Edgar Matobato, on the Davao Death Squad (DDS). Matobato alleged that he took orders to kill people from then-Davao City Mayor Rodrigo Duterte.
"Please mind your own business and don't ever tell the Philippine Senate on who should chair any of its committees," Pimentel added.
Aside from De Lima's ouster as Senate justice committee chair, the European Union's lawmaking body also condemned "the high number of extrajudicial killings" in the intensified campaign against narcotics.
The Senate president told European lawmakers to "step back" from the issue as the foreign chamber "has no right to micro manage" the Philippines.
Senate majority leader Vicente Sotto III echoed Pimentel's sentiment reminding the EU that it has "no business meddling" in the country's affairs.
"The EU must be reminded that we are a democratic nation with fully functioning laws and government," Sotto said.