Planned Parenthood announced Thursday that it will endorse Hillary Clinton for president -- the controversial group’s first political endorsement in its history.

The group, which has been under fire from Republicans after a number of controversies over its abortion practices, will formally endorse Clinton at a campaign event in New Hampshire on Sunday, Fox News confirmed.

The group announced the endorsement on Twitter, calling Clinton the “only candidate to speak up for Planned Parenthood at the debates” and cited her legislative record of “expanding and protecting access to reproductive health care.”

Clinton said in a statement she was "honored" to receive the endorsement.

"There has never been a more important election when it comes to women's health and reproductive rights-and Planned Parenthood's patients, providers, and advocates across the country are a crucial line of defense against the dangerous agenda being advanced by every Republican candidate for president," she said.

Fox News’ Jake Gibson contributed to this report.

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