The deployment's goal is to supplement California's existing efforts to "combat transnational crime", Brown said.
He has already won commitments for about 1,600 from the Republican governors of the other states that border Mexico- Arizona, New Mexico and Texas. They would join 250 existing California National Guard troops, including 55 who are at the border.
"Issues of border security require the partnership of the federal government and our state and local allies to be successful".
After days of speculation, California decided Wednesday that it will comply with federal requests to deploy National Guard personnel to the border California shares with Mexico.
The spokeswoman for President Donald Trump has welcomed the decision by California's Democrat governor to deploy 400 National Guard troops for a presidential request aimed at fighting illegal immigration and drug trafficking along the U.S. -Mexico border.
Unlike Republican governors in other border states, Brown disagreed with Trump's portrayal of a border spiraling out of control, noting that Border Patrol arrests fell to the lowest level previous year since 1971 and that California accounted for only 15 percent of the agency's arrests on the Mexican border. Brown while touring border wall prototypes in San Diego In the letter Brown said, "Let's be crystal clear on the scope of this mission". It will not be a mission to round up women and children or detain people escaping violence and seeking a better life.
Your funding for new staffing will allow the Guard to do what it does best: support operations targeting transnational criminal gangs, human traffickers and illegal firearm and drug smugglers along the border, the coast and throughout the state.
"This is not National Guard troops with rifles patrolling the border - it doesn't work that way", Krikorian said.
The governor also noted that the state guard "agreed to similar targeted assistance" under the past two presidents.
Border crossings for the past several years have been heading toward historic lows.
"Glad to have all four border governors working with us and the @USNationalGuard to secure the border", Nielsen wrote on Twitter after Brown's announcement. Trump followed with news that he would send 2,000 to 4,000 troops.
And fourth, the agreement Brown reached with the Trump administration will expire on September 30 - less than six months from now - unless both sides agree to extend it.