(Reuters) -The U.S. Supreme Court blocked on Tuesday a judge's order for President Donald Trump's administration to rehire thousands of fired employees, acting in a dispute over his efforts to slash the federal workforce and dismantle parts of the government. The court put on hold San Francisco-based U.S. Judge William Alsup's March 13 injunction requiring six federal agencies to reinstate thousands of recently hired probationary employees while litigation challenging the legality of the dismissals continues. Alsup's ruling applied to probationary employees at the U.S. Department of Defense, Department of Veterans Affairs, Department of Agriculture, Department of Energy, Department of Interior and the Treasury Department.