Washington, Feb 4 (IANS): The Pentagon has announced that it will deploy 3,750 additional US forces at the country's border with Mexico for 90 days to provide support to Customs and Border Protection (CBP) officials.

The Department of Defence said in a statement on Sunday that the additional forces will raise the total number of active duty troops supporting the CBP at the border to about 4,350, reports NBC News.

The support they will provide includes "mobile surveillance capability" and the placement of "approximately 150 miles of concertina wire between ports of entry", the statement said.

The additional forces were approved by Acting Secretary of Defence Patrick Shanahan on January 11.

On January 29, Shanahan said the US would be sending "several thousand" more troops to the Mexico border.

The move comes as another caravan of asylum seekers and migrants from Central America has been making its way to the US border.

President Donald Trump tweeted about the caravan on Sunday, saying "if there is no Wall, there is no security", NBC News reported.

Last week, the Trump administration also began its new policy of sending some migrants seeking asylum back to Mexico while they await court hearings that are set to take place in San Diego.

The Pentagon had announced last October that it would deploy an additional 5,600 troops to the border in the wake of a caravan making its way to the US that month from Central America.

Thousands of migrants have since been waiting weeks or months to seek asylum in the US, often waiting in shelters and in poor conditions.

Any additional forces deployed by the US are not allowed to apprehend migrants the way border agents do.

Sunday's announcement is separate from the potential White House-led effort to use existing Pentagon funds or personnel to help build new sections of a border wall with Mexico.