Mexican lawmakers blocked on Wednesday divisive electoral reforms proposed by President Andres Manuel Lopez Obrador that sparked mass street protests but advanced other changes on Wednesday.

On Tuesday, the lower house of Congress rejected an electoral reform backed by Lopez Obrador, who needed support from at least two-thirds of lawmakers to change the constitution. The reform received 269 votes in favor, 225 votes against, and one abstention.

The Mexican President sought to push through reforms, including a reduction in the budget of the National Electoral Institute (INE), the independent body that organizes the country's elections.

Lopez Obrador's "Plan B", which required approval by a simple majority of lawmakers, was passed in the Chamber of Deputies by 261 votes in favor and 216 against.

The opposition Institutional Revolutionary Party considered the changes a "betrayal of Mexico."

The proposals must still be approved by the upper house, the Senate, where the ruling party and its allies also have a majority.

Last month, tens of thousands of demonstrators marched in Mexico City demanding a halt to the proposed reforms.

Lopez Obrador argued that the INE endorsed fraud when he ran unsuccessfully for the presidency in 2006 and 2012, before winning in 2018.

Under his initial plan, the INE would have been replaced by a new body with members chosen by voters instead of lawmakers.

The number of seats in the lower house of Congress would have been reduced from 500 to 300, and those in the Senate from 128 to 96.

Lopez Obrador, who has an approval rating of nearly 60% but is barred by the constitution from running for a second term, believes that his reform plan sought to "strengthen democracy".

He dismissed the opposition protest against his proposal and two weeks later led hundreds of thousands of his supporters on a march through Mexico City.

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