Leni Robredo ready to challenge President Rodrigo Duterte as opposition leader

Vice President Leni Robredo (left) with President Rodrigo Duterte (right) on July 1, 2016 in Quezon City.
Gregorio B. Dantes Jr./ Pacific Press / LightRocket / Getty Images

President Rodrigo Duterte could have an unlikely opposition leader in the Philippines' legislature: one of his own ministers.

Philippine Vice President Leni Robredo told local news outlets on Monday that she was ready to head up a new opposition party. Her comments came a day after she resigned as housing secretary, a position she was appointed to in July by Duterte himself; vice presidents are allowed to take on concurrent posts in cabinet if the president chooses, according to the constitution.

"I will continue to fight against things I do not believe in. If being an opposition leader entails that, then I will be an opposition leader," local media quoted Robredo as saying on Monday.

The 52-year-old's Liberal Party is currently allied with Duterte's PDP-Laban party in congress. But if the Liberal Party left the alliance, it could become an official opposition party, with Robredo at the helm, politician Teddy Baguilat said, according to local news.

Unlike other democracies, candidates for the presidency or vice presidency in the Philippines are elected separately so it's possible for the people in the roles to come from different parties.

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The nation currently lacks a strong opposition and the prospect of more powerful resistance to Duterte comes amid fears of growing authoritarianism in his administration.

In a statement on Sunday, Robredo said she stepped down due to "major differences in principles and values" with Duterte, and that the "last straw" came on Saturday, when she received a text message from Cabinet Secretary Jun Evasco that instructed her to stop attending cabinet meetings.

"Her resignation gives us a strong sense that the president does not like to work with people who criticize him or his agenda," Jean Franco, assistant professor at the University of the Philippines, told CNBC. Franco believes Robredo will be a successful opposition leader mainly due to her untainted public image and charisma.

Robredo, a former human rights lawyer, has been a high-profile critic of the president, having called for an investigation into allegations of extrajudicial killings amid the state's five-month old war on drug trafficking. Human Rights Watch estimates the death toll at about 5,000, while police put the number of people killed by officers in self-defense at 2,400, according to a Reuters investigation published this week.

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Robredo also objected to Duterte's decision to bury former president Ferdinand Marcos in a cemetery reserved for national heroes. Marcos committed numerous human rights abuses during his 20-year reign and thousands in Manila protested against the dictator's burial last week.

The apparent order that Robredo stay away from cabinet meetings is not the first time Duterte has sidelined a critic during his short time as leader.

In September, the senate removed Leila de Lima, a former justice secretary in the previous administration, who has also been openly critical of Duterte, from her post as head of a committee investigating the claims of extrajudicial killings. At the time, analysts said the move was a clear attempt to silence Duterte's critics in government.

A purge of senior officials who failed to express support for Duterte's agenda may now be underway, said Citi economist Jun Trinidad in a note on Monday.

But if Robredo took on the new role as opposition leader, she faces a tough task in matching the president's popularity.

"She may be the new opposition's symbol and her resignation may elicit sympathy support, but it's unlikely to elevate her to Duterte's demi-god status," Trinidad explained.

"Her popularity is best gauged by her narrow election victory (260,000 votes) against her closest rival, Senator Ferdinand Marcos Jr. [son of the late president Marcos]," he added.

Moreover, she may face the wrath of Duterte's propaganda machine.

"Expect broadsides highlighting her allegedly jet-setting life and her penchant for appearing in magazine covers…Memes are already abound that she is busy hobnobbing with high society," warned Joseph Franco, research fellow at Singapore's Nanyang Technological University.

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