Sen. Rand Paul, a well-known ally of President Donald Trump, has thrown an unexpected wrench into one of Trump’s Cabinet confirmations.

The Kentucky Republican announced this week that he will not support Trump’s nominee for Secretary of Labor, Lori Chavez-DeRemer.

Paul told Fox News Radio correspondent Ryan Schmelz and NBC News senior political reporter Sahil Kapur that he intends to vote “no” on Chavez-DeRemer’s confirmation, citing concerns over her “very pro-labor” stance. “I think she’ll lose 15 Republicans and she’ll get 25 Democrats,” he told Schmelz. “I mean, she’s very pro-labor. She might get all the Democrats. Who knows.” 

Trump nominated Chavez-DeRemer as his Secretary of Labor in November, highlighting her support for American workers.

“Lori’s strong support from both the Business and Labor communities will ensure that the Labor Department can unite Americans of all backgrounds behind our Agenda for unprecedented National Success,” he wrote. “Making America Richer, Wealthier, Stronger and more Prosperous than ever before!”

Republicans are sounding the alarm that Tulsi Gabbard’s path to confirmation as head of the U.S. intelligence apparatus is narrowing as she struggles to win over key GOP senators.

Gabbard, along with Robert F. Kennedy Jr. and Kash Patel, is set to undergo high-stakes confirmation hearings this week as the Senate weighs some of President Trump’s most controversial nominees, The Hill reported.

Gabbard faces an uncertain path to confirmation as she seeks to win over skeptical Republicans on the Senate Intelligence Committee, which will determine her fate ahead of Thursday’s hearing.

“I think it remains to be seen,” said Sen. John Cornyn (R-Texas), an Intelligence Committee member, when asked if Gabbard can win support of the panel. “I think the jury’s still out.” Another Senate Republican agreed, telling The Hill that Gabbard “has a path [that] continues to narrow.”

The former Democratic congresswoman from Hawaii, who is currently serving as an Army Reserve officer, cannot afford to lose any votes on the Intelligence Committee.

The committee has a Republican majority of 9-8, and it includes two GOP senators who are considered swing votes: Susan Collins from Maine, who voted against another nominee from Trump on the Senate floor last week, and Todd Young from Indiana.