FILE PHOTO: Mexico's President Andres Manuel Lopez Obrador attends a news conference at the National Palace in Mexico City, Mexico June 10, 2019. REUTERS/Gustavo Graf/File Photo

MEXICO CITY (Reuters) - Mexican President Andres Manuel Lopez Obrador on Tuesday proposed holding a recall referendum on his presidency on March 21, 2021 if Congress cannot agree to a constitutional change permitting the vote during mid-term legislative elections.

Lopez Obrador took office in December vowing to give the public a chance to vote him out of office halfway through his six-year term, but the plan has met resistance in the Senate from opposition lawmakers concerned about its implications.

“What do I propose?” he asked reporters at his regular morning news conference. “That if doing it on the same day as a the federal election is not accepted, which would be the best thing ... that the recall referendum is brought forward without any additional cost. I’m proposing March 21st, 2021.”

The Senate is due to debate Lopez Obrador’s recall plan this week, when it will be in session to consider ratifying the United States-Mexico-Canada-Agreement to replace the North American Free Trade Agreement.

Critics say the proposed recall amendment would let Lopez Obrador put himself at the center of the campaign for mid-term federal elections, which should be held in June 2021, and could be used to encourage support for permitting presidential re-election, which has long been a taboo in Mexico.

The constitution limits Mexico’s president to a single six-year term. Not permitting re-election has been a principle of Mexican politics since Francisco Madero campaigned in 1909 against Porfirio Diaz, who held on to power for three decades.

Several Latin American leaders have changed laws to allow them to be re-elected, including leftists such as Venezuela’s late President Hugo Chavez and President Evo Morales in Bolivia.

Former right-leaning Colombian president Alvaro Uribe also engineered a constitutional change so he could run for re-election.