Gutierrez has become unpopular since winning power in 2002

Opposition parties needed the support of 51 of 100 members to begin a case against Mr Gutierrez, whom they accused of corruption in an election campaign.

But several Congressmen refused at the last minute to vote for impeachment.

Supporters of Mr Gutierrez claimed the three changed their minds because of effective lobbying by the government.

Plans to set up a special committee to impeach the president last week won the support of 51 members from a number of opposition parties.

But at a vote on Tuesday, two members of the Social Christian party, the largest group in Congress, withdrew their support at the last minute.

Several other opposition members refused to vote.

Shaky alliances

Social Christian leader Leon Febres Cordero accused Mr Gutierrez of bribing members to switch their votes: "Gutierrez claims to be combating corruption and at the same time he is determined to shamelessly buy consciences."

Energy Minister Eduardo Lopez said the members refused to vote "for the sake of democracy".

On Wednesday, the Social Christians changed tack, insisting it was "not the right time" to push for impeachment, Reuters reported.

The party accused the president of embezzling state funds to campaign for local elections in October, as well as risking national security by requisitioning state-owned transport for the campaign.

Mr Gutierrez, a former head of the army, was elected president in November 2002 after winning support from Indian leaders.