MEXICO CITY (Reuters) - Mexico’s Lower House on Thursday approved a constitutional reform that would allow for referendums to cut short the six-year presidential term, a move opposition lawmakers say opens the door to allowing re-election to the nation’s highest office.

Mexico's President Andres Manuel Lopez Obrador speaks to the media during a news conference to announce a plan to strengthen finances of state oil firm Pemex, at the National Palace in Mexico City, Mexico February 15, 2019. REUTERS/Henry Romero

President Andres Manuel Lopez Obrador, who took office on Dec. 1, said during the campaign that he would hold a referendum on his performance at the middle of his term and would cut it short if he loses the consultation.

Lopez Obrador’s MORENA party and its allies hold majorities in both chambers of Congress. The constitutional reform received the required support of two thirds of lawmakers in the Lower House. It now goes to the Senate for discussion and a vote.

“These changes will allow the Executive (branch) an intense political campaign in a shameless way in 2021 just when this chamber and 13 governorships are renewed,” said opposition lawmaker Xavier Azuara, from the PAN party.

It is a “path to re-election,” Azuara said.

Recent polls have shown Lopez Obrador has the support of almost four out of every five voters.

The constitutional reform also makes it easier to hold popular referendums, which Lopez Obrador has used to put infrastructure projects and other social programs to a vote by citizens.

That practice has riled markets since the leftist party swept to power last year.

In October, Lopez Obrador pulled the plug on a part-built, $13 billion new airport for the capital after citizens voted down the project.

Only about 1 percent of the Mexican electorate participated in the referendum, and critics slammed the process as unfair. Mexico’s stock exchange and peso tumbled after the decision was announced.