Former President now House Speaker Gloria Macapagal Arroyo disputed Monday claims by critics from the Senate that the budget bill the House of Representatives approved and transmitted to the Senate is illegal.

In an ambush interview at the Batasan Pambansa, Arroyo said congressmen "would never put the President in the position of signing an unconstitutional bill."

"It's the same process that was done even before I was Speaker ever since the Supreme Court ruled that lump sums were unconstitutional. We cannot agree to a lump sum allocation," she said.

Senate President Tito Sotto and Sen. Panfilo Lacson have said the 2019 budget bill is illegal because it contained itemization of lump sums done after the ratification of the bicameral conference committee report, supposedly the last act of Congress before a budget bill is sent to the President for final signature.

Lacson told reporters Arroyo could be charged with falsification for signing the House version of the enrolled bill. "She's already certified something that did not take place. Certify mo ito, approved sa plenaryo. Pareho ng niratify naming bicam report sa Senate," he said.

"Hindi consummated ang General Appropriations Act but the act of signing a falsified document is already consummated. So any taxpayer can go to the Ombudsman or Department of Justice to file a criminal complaint against her for falsification," he added.

For his part, House Majority Leader Fredenil Castro defended Arroyo for pushing the agenda of President Duterte in the House of Representatives and accused the Senate of obstructing the passage of the 2019 budget.

Former Budget Secretary and now House appropriations committee chair Rolando Andaya Jr., meanwhile, accused senators of hiding funds in the 2019 budget via lump sum appropriations.

“Mukhang malaki ang tinatago ng ating mga senador kung kaya ayaw nila ng itemized budget ng House of Representatives at mas gusto nila sa lump sum na ilegal at maaaring abusuhin para sa katiwalian," he said.

He also accused the Upper Chamber of removing P12 billion from the public works and highways department budget and P5 billion from the transportation department budget.

"Ang Senado at hindi ang House of Representatives ang humaharang sa mga programa ni Pangulong Duterte, lalo na sa kanyang Build Build Build program. Sino ba ang nagkaltas ng P17 bilyon sa right of way ng DPWH at DOTr para sa Build Build Build Program? Ang Senado ang nag-alis ng P17 bilyon para sa right of way funding ng Build Build Build projects ng Pangulo," he said.

He added that Line-itemized budgeting by the House will not cripple President Rodrigo Duterte's Build, Build, Build Program.

"What may stall the acceleration of the infrastructure spending was the Senate's unilateral decision to remove P17 billion for the right-of-way funding of BBB projects. On the contrary, the Senate's removal of P17-billion worth of right-of-way funding will be the greatest stumbling block for the President's infrastructure master plan. Without the knowledge of and consent from the House of Representatives, the Senate removed P12 billion of these funds from the DPWH and P5 billion from the DOTr. How can projects be started without these right-of way-payments? Billions of pesos worth of roads will never begin construction even if these projects are fully-funded," he said.

"Saan ba talaga napunta ang mga pondong ito? Up to this very moment, the senators are also silent on who are the individual proponents for their realignments. These realignments were made after both chambers ratified the bicameral conference committee report on the 2019 national budget," he added.