Two states have answered the call from President Trump to have National Guard stationed at the Mexican border with the U.S. in order to help enforce immigration law.

Here's who answered the call

A spokesman for the Texas National Guard said Friday that they would be sending 250 troops to the border as part of an “initial surge." Arizona Gov. Doug Ducey also announced that his state would send 150 troops next week to the border.

The president had announced that he was willing to send the military to the border in lieu of his plan to build a wall after his efforts were frustrated by Democrats in Congress.

Trump has said he wants 2,000 to 4,000 guardsmen to go to the border - Texas and Arizona will account for just 400 of those so far.

Due to constitutional limits on the executive use of the military within the nation's borders, the National Guard would still be technically under each state's governor's command.

That results in some states like Texas and Arizona answering the call, while others like Oregon are vocally refusing the demand from the president.

Not the first time

Although Trump is being lauded for the effort to curtail illegal immigration through the use of the National Guard, he is not the first president to do so in recent history. Both his predecessors former presidents George W. Bush and Barack Obama sent National Guardsmen to the border. Bush sent 6,000 in 2006 and Obama sent 1,200 in 2010.

Here's a Fox News report about National Guards at the border: