Spokesmen for the Democratic Revolution Party (PRD) and the United Progressive Front (FAP) rejected Calderón´s written effort to establish common cause on key legislative and policy issues.

"The fundamental difference between our project and his is that we believe he did not win the election," said PRD spokesman Gerardo Fernández Noroña. "As such, he does not deserve any consideration or respect and we will never take any steps to contribute to his project."

Fernández also reiterated his party´s determination to prevent Calderón from taking the oath of office on Dec. 1.

For his part, Jesús Ortega, the spokesman for the FAP, said Calderón´s letter was too superficial and failed to address critical social issues.

"The letter did not even mention key challenges for the country, such as the need to put an end to the dominance of monopolies in critical sectors," he said. "I also saw no reference to comprehensive electoral reform."

Ortega also criticized the president-elect for failing to address the recent price rises in the subsidized milk program and for premium and diesel gasoline.

When asked if the FAP would answer the letter, Ortega demurred: "There is no reason to respond. Legislative issues will be debated in Congress."

Fernández said the PRD would not respond to the letter either.

"We have no intention of opening a dialogue with him. We will stick to our decision to open talks only with political parties at the legislative level," he said.

EL UNIVERSAL writer Jorge Herrera contributed to this report.