MANILA, Philippines -- (UPDATE 9) Jose de Venecia Jr., facing an increasing likelihood of his ouster as speaker of the House of Representatives, told reporters Monday that he would join the political opposition and was declaring ?war? on erstwhile ally, President Gloria Macapagal-Arroyo.

De Venecia spoke to reporters after delivering an impassioned speech in the House plenary hall, accusing Malacañang of orchestrating moves to remove him as House speaker. After he took the floor, the House began an open vote on whether to declare the position of speaker vacant and effectively unseat him.

The 240-member House needs 121 votes to remove De Venecia from the position he has held for five consecutive three-year terms, considered the longest in Philippine history. At 10:45 p.m., more than 110 members of the House had voted ?yes? to declare the speakership vacant, 25 voted ?no,? and six abstained.

In a 59-minute speech, De Venecia recounted the times he had stood to defend President Arroyo, and said, ?It pains me grievously to hurt the President and to hurt the First Family because I have invested so much more than any of you in this chamber to help the President become Vice President, become President?.?

In an interview after his speech, reporters asked De Venecia whether his accusations against the President, members of her family and close associates were a declaration of war. He replied, ?Yes.?

?I will join the opposition to denounce corruption in this administration. I will join the battle against corruption,? he said.

In his speech, De Venecia said that Malacañang was in "collusion" with a private lawyer who had filed several complaints against him and his son, Jose ?Joey? De Venecia III, before the Ombudsman.

He was referring to lawyer Roel Pulido, who had also filed an ethics case against him at the House.

He added that congressmen could not use proceeds of the road users' tax without going through agents of Malacañang.

He accused the presidential palace of inaction on alleged assassination threats against him and his son, who has alleged bribe offers in connection with a contract to put up a multimillion-dollar national broadband network.

Before ending his speech, De Venecia also identified port magnate Enrique Razon, who served as treasurer of Arroyo?s senatorial candidates last year, as having control of the pork barrel, road users? tax funds and many projects of the administration.

He described Razon as ?partner in the corridors of power in Malacañang.?

Before De Venecia took the floor, a heated debate on whether to allow him to deliver a personal speech ensued when session resumed after it was suspended for almost an hour.