Two leftist parties and the conservative National Action Party, or PAN, have joined forces to take on the Institutional Revolutionary Party, or PRI, in the Mexican Senate, announcing the creation of a broad front to fight the "authoritarian practices of the past."

PAN chairman Gustavo Madero and Party of the Democratic Revolution, or PRD, chairman Jesus Zambrano were joined by other party officials, as well as a lawmaker from the Citizens Movement, in forming the front.

The front's goal is to "combat the excesses of authoritarianism, as well as the corrupt practices ... of the past," the PAN said in a statement.

The leftist and PAN senators joined forces to push for labor law reforms that were blocked by the PRI in the Chamber of Deputies, the lower house of Congress.

The bill was submitted to Congress by President Felipe Calderon, of the PAN, on Sept. 1.

The legislation would introduce democratic reforms and transparency to labor unions, the majority of which are allied with the PRI.

President-elect Enrique Peña Nieto, of the PRI, will be inaugurated on Dec. 1. EFE