BRASILIA, Feb 1 (Reuters) - Brazil's Congress elected a conservative as speaker of the Chamber of Deputies on Sunday in a setback for the ruling Workers' Party that split President Dilma Rousseff's coalition and will complicate her legislative agenda.
Eduardo Cunha belongs to Brazil's largest party, the PMDB, Rousseff's main ally in the governing coalition, but he defeated a Workers' Party candidate by advocating for a legislature that was less subservient to the government.
Cunha backs a bill that would make it harder for the federal government to block spending proposed by lawmakers, which would counter Rousseff's efforts to eliminate Brazil's fiscal deficit with austerity measures as she begins her second term.
"We seek the independence of Congress. We will not become opponents of the government, but we won't be submissive either," he said. Rousseff still enjoys a majority that ensures her government's stability, he added.
Rousseff, however, will not be able to count on Cunha to shield her administration from renewed congressional inquiries into a corruption scandal at state-run oil company Petroleo Brasileiro SA. that threatens to implicate members of her party. Rousseff has denied any knowledge of the scheme though she was chairwoman of the company's board when much of the alleged graft took place.
Cunha also opposes a controversial plan by the Worker's Party to regulate Brazilian media.
The new speaker, a 56-year-old economist who follows the Evangelical faith, is known for doggedly representing the interests of lobby groups in negotiating legislative proposals, which has often put him at odds with Rousseff's policies.
His critics have dubbed him Brazil's Frank Underwood, in reference to the ruthless politician in the American television series "House of Cards."
Earlier on Sunday, the Senate re-elected a loyal Rousseff ally, Renan Calheiros of the PMDB party, as president of the upper chamber.
The heads of the Chamber of Deputies and the Senate are third and fourth in the line of presidential succession.
They will preside over a more fractious Congress with 28 parties, fewer members representing labor and environmental interests, and more Christian conservatives and farm lobby representatives. (Reporting by Anthony Boadle; Editing by Sandra Maler)