The Catholic Bishops Conference of the Philippines' (CBCP) repudiation of current efforts to change the 1987 Constitution through a people's initiative has been dealt a "fatal blow" on the administration's Charter change efforts, Senate Minority Leader Aquilino Pimentel said on Saturday.

"The anti-Charter change statement of the CBCP puts the last nail into the coffin of Cha-cha efforts of President Gloria Macapagal-Arroyo, Speaker Jose de Venecia Jr., [Interior] Secretary Ronaldo Puno, et al.," Pimentel said.

He expressed doubts the administration's Cha-cha campaign "could withstand the deadly impact" of the CBCP's pastoral statement.

The CBCP issued a pastoral letter on Friday warning that the move to amend the Constitution for a shift to a parliamentary system was "dangerously unclear and open to manipulation by groups and self-serving interests" and that "vigilance, education, [and] principled opposition may be necessary steps to take."

Pimentel said that the Arroyo administration could not afford to lose the support of the Catholic Church or go into an open confrontation with its hierarchy.