A U.S. appeals court on Thursday placed a brief pause on a judge's ruling that had blocked President Donald Trump's administration from stripping hundreds of thousands of federal workers of the ability to engage in union bargaining with U.

But a May 22 move by the Supreme Court may signal the end of the NLRB’s independence, say labor leaders, and transform the agency into an extension of the White House. In turn, they warn, President Donald Trump could use the board to reward friends and punish enemies.