A Philippines congress committee has delayed a vote on which of three impeachment complaints to take up against President Gloria Arroyo.
The justice committee is dominated by Mrs Arroyo's supporters
The committee has instead voted to spend more time debating procedural issues first.
Opposition politicians said the development would lead to massive delays in the process.
Mrs Arroyo faces accusations of corruption and electoral fraud. She denies any wrongdoing.
The House of Representatives justice committee reportedly decided there were "prejudicial questions" that would preclude them from immediately hearing the three complaints against her.
Opposition legislator Alan Peter Cayetano said this would further slow the impeachment proceedings.
"We can expect massive delays. We can expect additional questions instead of going straight to the question," of whether Arroyo can be impeached, Mr Cayetano said.
The committee is dominated by Gloria Arroyo's supporters, and is expected to ultimately choose the weakest of three complaints against her to consider.
The committee will then decide whether to send the complaint to the House of Representatives, then the Senate, which could remove her from office.
Accused of using position to influence 2004 poll
Husband accused of influence-peddling and taking bribes
Son and brother-in-law also implicated
Family denies all allegations
She has denied any wrongdoing, but admitted to "a lapse of judgment" over a telephone conversation with an electoral official during last year's bitterly contested presidential election.
She maintains, however, that she was not trying to influence the results.
The justice committee is expected to choose to take up what is seen as the weakest allegation against Mrs Arroyo - that she betrayed public trust during last year's election.
The other two complaints include allegations that her family profited from illegal gambling.
Once the committee has decided which option to pursue, it will decide whether to send the complaint on to the House of Representatives, the lower house.
The motion must be endorsed by at least a third of the House of Representatives before it can be sent to the upper house, the Senate, for a final vote.
Justice committee to decide on a complaint, and consider whether to take it further
Complaint then needs support of one-third of 235 lawmakers in lower house
If it gets that, upper house votes on motion
Support of two thirds of 23-member upper house will remove Arroyo from office
A conviction by two-thirds of the Senate would lead to the president's dismissal.
Opposition leaders in the lower house said on Tuesday that they still lacked the required support of 79 lawmakers - one-third of the 235-strong assembly.
"We won't reveal the names until we reach 79. Rest assured, it's more than the 42 that initially signed the amended complaint," House of Representatives leader Francis Escudero told the media on Tuesday.
The BBC's Sarah Toms in Manila says the opposition was initially reluctant to pursue the impeachment route because of the president's majorities in both houses, but since the defection of some of Mrs Arroyo's allies, her opponents have warmed to the idea.
There have been regular street protests against the president in recent weeks, but the largest such crowd has fallen far short of the hundreds of thousands which joined the "people power" uprisings that overthrew President Ferdinand Marcos in 1986 and Joseph Estrada in 2001.