President Donald Trump issued an executive order to halt pay hikes for many federal employees for 2019.

The pay freeze -- which would not include the military and some others on the federal payroll -- comes during the partial shutdown of the U.S. government.

The order also knocks over an earlier Senate-approved 1.9% pay increase plan for federal workers, and moves forward with an earlier proposal by the president.

"This is just pouring salt into the wound," said Tony Reardon, president of National Treasury Employees Union, in a statement. "It is shocking that federal employees are taking yet another financial hit. As if missed paychecks and working without pay were not enough, now they have been told that they don't even deserve a modest pay increase."

Some 150,000 employees in 33 federal agencies and departments are represented by the union. 

Not only does the move come just a couple weeks into the shutdown that has cast the livelihood of hundreds of thousands of federal employees into uncertainty, it also comes days after the president implied in a Twitter post that most of the federal workers are Democrats.

"Do the Dems realize that most of the people not getting paid are Democrats?," he said in a post on Thursday, about the shutdown.

In a letter to lawmakers in August, however, Trump argued restricting pay hikes was necessary, "in light of our Nation's fiscal situation."

 "As noted in my Budget for Fiscal Year 2019, the cost of employing the Federal workforce is significant," Trump stated, noting that federal employee pay should be based on performance, and for "recruiting, retaining, and rewarding" workers who are skilled and dedicated.

"Across-the-board pay increases and locality pay increases, in particular, have long-term fixed costs, yet fail to address existing pay disparities or target mission critical recruitment and retention goals."

The shutdown is part of an ongoing battle to include billions of dollars in funding for a wall along the U.S. border with Mexico, which was a central promise during Trump's campaign. 

This article was written by a staff member of TheStreet.