WASHINGTON (CBSDC/AP) — In a public rebuke to President Barack Obama, top House Democrat Nancy Pelosi on Friday swung against legislation aimed at making it easier for the president and his successor to negotiate free trade deals.

The California Democrat said lawmakers should “slow this down” in hopes of getting stronger protections for U.S. workers and the environment in potential trade pacts, including one with Pacific nations.

Pelosi made her position known just prior to separate House votes to reject aid to displaced workers and to give Obama the “fast track” trade negotiating authority he is seeking.

“We need to slow this ‘fast track’ down,” Pelosi said.

Pelosi had been seen as a silent ally to Obama and Republicans running the House in promoting Obama’strade agenda, though she kept her position secret until the end of Friday’s debate. She made clear she’s open to supporting future trade legislation, noting that she represents a San Francisco district that thrives on trade and grew up in Baltimore, home of a thriving port.

Pelosi voted “no” despite escorting Obama into a closed-door caucus of House Democrats, most of whom opposed the fast-track trade bill, which requires that trade pacts be delivered to Congress for up or down votes, without amendment. The authority is key to getting trade partners to seal agreements since they know Congress can’t amend them.

One House Democrat told CNN’s Jake Tapper that Obama became “indignant.”

“He was fine until he turned it at the end and became indignant and alienated some folks,” the lawmaker said.

Another Democratic House lawmaker told Tapper that Obama’s visit “absolutely” hurt the bill.

“Democrats believe they often are taken granted and not appreciated” by Obama, the lawmaker said.

The California Democrat was in a tough spot, torn between loyalty to a president whose agenda she supports and a Democratic caucus strongly tilted against Obama in this instance.

“She’s in a really difficult situation,” said pro-trade Rep. Henry Cuellar, D-Texas. “She doesn’t want to see the president fail. At the same time, she understands that there’s a lot of folks — labor and other folks, other progressive groups, and some members that feel strongly.”

Pelosi said “I’ve been very prayerful on this.”

Pelosi also voted against legislation to aid workers who lose their jobs because of trade deals, not because she opposed it but because its passage was directly linked to advancing the subsequent trade negotiating measure.

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