MANILA - Senate President Aquilino "Koko" Pimentel III said Wednesday he will try to settle the feud between Senators Leila de Lima and Richard Gordon.

Gordon earlier accused De Lima of “material concealment” when the latter failed to bring up the information that self-confessed Davao Death Squad hitman Edgar Matobato was charged of kidnapping by the common-law wife of slain alleged terrorist Sali Makdum .

De Lima, however, noted that Matobato himself had revealed the information during the September 15 Senate hearing.

Furious over the allegation, De Lima walked out of the hearing last Monday and demanded an apology from Gordon, who heads the Senate Committee on Justice probing the extra-judicial killings and the alleged existence of the DDS.

Refusing to back down, Gordon said he will file an ethics complaint against De Lima and her fellow senator Antonio Trillanes IV over their “unparliamentary acts.”

Pimentel said that while the Senate has a system for complaints of "unparliamentary conduct," he said he has started to reach out to the two senators.

"Nothing is impossible in the Senate. We should learn to co-exist with each other," said Pimentel.

Senate Majority Leader Tito Sotto also said the differences between the two can be settled within the "supermajority." He, however, noted that according to Section 93 of the rules of the Senate, a complaint of "unparliamentary conduct" may be filed by a senator against a colleague.

"Acts and languages that offend a senator is unparliamentary conduct," said Sotto.