Perez, who personally handed the letter of request to the Office of the Ombudsman Visayas said, "kinahanlang g'yud makig-audience mi niya (Santiago) ASAP (as soon as possible)."
"(I) hope the anti-graft office can provide us (with) updates on their ongoing investigation into this matter," he added.
Perez stressed that there is a need to resolve the controversy to "seek the truth, accountability and transparency especially in the light of public clamor for the transparent liquidation of the expenses on the summit hosting."
Bayan Muna and its allied militant groups earlier filed a complaint before the anti-graft office against the Department of Public Works and Highways officials over the alleged questionable acquisition of decorative lampposts.
The party-list group had also filed a congressional resolution urging all concerned parties to give a full account on the government's reported "lavish" hosting of the summit from January 10 to 15.
Perez also supported the move of Pelican Group in filing a civil case before Regional Trial Court Judge Eric Menchavez against the DPWH and Triton Communications, the supplier of the surveillance cameras.
Pelican Group was the winning bidder for the installation of the surveillance cameras but its contract was rescinded by DPWH after it reportedly failed to deliver the equipment on time. - Ramil V. Ayuman