United President Donald Trump on Wednesday signed a proclamation directing the National Guard to be deployed to the Mexico border, AP reported. The president’s move to deploy troops along the border comes after he failed to persuade the US Congress or the Mexican government to fully fund a wall that he had claimed to build along the border.

The National Guard is a reserve military force, part of the US Armed Forces, and is under the control of both the state and the federal government.

In a memorandum to his secretaries of defense and homeland security, the president said the situation at the border has “now reached a point of crisis”. The memorandum asked the Secretary of Defence to support the Department of Homeland Security in securing the southern border to stop the flow of drugs and people.

Trump claimed that lawlessness at the southern border is “fundamentally incompatible with the safety, security and sovereignty of the American people,” AP reported.

The National Guard will also help US Customs and Border Protection personnel stop illegal immigrants from entering the country, Homeland Security Secretary Kirstjen Nielsen told reporters. She said the administration does not have a date for the national guard to be deployed. The function of the National Guard on the border would cover everything, including aerial surveillance, she added.

“Border security is homeland security, which is national security,” Nielsen said. “It is not a partisan issue. It is not something we can separate out. It is core to being a sovereign nation.”

Meanwhile, the Mexican government has told Washington that if the deployment of troops turned into a “militarisation of the border”, it would damage the bilateral relationship between the countries, Reuters reported. The Mexican government said Nielsen had discussed the plan with Mexican Foreign Minister Luis Videgaray and told him the troops will not carry arms.

Between 2006 and 2008, then President George W Bush had deployed the National Guard to provide border-related intelligence analysis, but it had no direct law enforcement role. In 2010, President Barack Obama sent the National Guard to the US-Mexican border to provide surveillance and strategic support to the US Border Patrol agents.