As the 2016 Democratic National Convention kicks off, Debbie Wasserman Schultz resigned as DNC chair under pressure after a massive cache of leaked internal emails suggested the party was siding with Hillary Clinton in the primaries.

The 49-year-old South Florida congresswoman came under withering scrutiny in the middle of a growing controversy over the trove of hacked emails exposed by WikiLeaks.

The leak raised questions over the DNC's impartiality as Clinton was locked in a tense primary battle with Vermont Sen. Bernie Sanders . The exposed missives showed DNC staffers collaborating with Clinton even as they attempted to undermine Sanders' presidential bid, which began as quixotic but gathered momentum.

Wasserman Schulz, an 11-year congressional veteran, will step down after the Democrats conclude their convention at the end of the week. DNC vice chair Donna Brazile, a political vet who ran Al Gore's 2000 White House bid, will serve as interim chair until a permanent replacement is selected, the party organization said.

"I know that electing Hillary Clinton as our next president is critical for America's future," Wasserman Schultz said in her resignation statement Sunday. "I look forward to serving as a surrogate for her campaign in Florida and across the country to ensure her victory."

Earlier in the day, CNN reported that Wasserman Schultz would not preside over the convention based on a decision made by Democratic officials who were trying to contain the fallout from the scandal.

"She's been quarantined," an unnamed senior Democrat told CNN on Sunday about Wasserman Schultz.

Wasserman said she would assume her ceremonial duties of opening and closing the event, as well as speaking to the delegates.

"We arrived here in Philadelphia with the most inclusive and progressive platform the party has ever proposed and a unified recommendation from the Rules Committee on our path forward as Democrats," she said. "I am proud of my role in leading these efforts.

Yet with the WikiLeaks controversy swirling, it raised the possibility that Sanders supporters might not be assuaged by the resignation. Many of his backers felt the DNC unfairly favored Clinton in the primary, and Sanders himself was a fierce critic of the congresswoman.

In a statement after her resignation, Sanders called on the party to promote "new leadership that will open the doors of the party and welcome in working people and young people.

"The party leadership must also always remain impartial in the presidential nominating process, something which did not occur in the 2016 race," he added.

The emails show DNC staffers disparaging the Sanders' campaign, as well as the candidate himself. The senator has been a sharp critic of Wasserman Schulz, whom he accused of favoring Clinton's candidacy from the outset.

In a statement, President Barack Obama said Wasserman Schultz played a "critical role in supporting our economic recovery, our fights for social and civil justice and providing health care for all Americans," he said. He called her a "dear friend."

Clinton also referred to the congresswoman as a friend. Wasserman Schultz is facing re-election in November, and the presumptive Democratic nominee said she would back Wasserman in that effort.

"I look forward to campaigning with Debbie in Florida and helping her in her re-election bid — because as President, I will need fighters like Debbie in Congress who are ready on day one to get to work for the American people," Clinton said.

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