Updated

There was a significant dip in illegal immigration across the southwest border during President Trump’s first month in office compared to that of the last three months of Obama’s presidency, the U.S. Customs and Border Protection (CBP) said.

In January, 31,575 individuals were taken into custody between ports of entry on the southwest border. That contrasts with an average of more than 45,000 for each of the previous three months, according to a CPB report released Monday.

The agency said that while it is experiencing a decrease in illegal attempts at entry, the overall total migration remains at elevated levels due to family units and unaccompanied children from three groups: Central Americans, Haitian nationals migrating from Brazil and Cuban nationals.

Jim Carafano, a security expert with the Heritage Foundation, said an assortment of factors could account for the change in numbers.

“There are a lot of reasons why numbers go up and down, but some of it could be a reaction to statements from President Trump that we’re going to increase border security and seeing media reports that we’re going to get tougher on illegal immigration in the U.S. People may be more resistant to come,” Carafano told Fox News.

“You can’t make too much of monthly numbers, but if you see the total lawful immigration population drop, that means you’re doing something that’s impacting the system overall.”

A senior Trump administration official said Tuesday that the president is considering legislation to provide a pathway to legal status, but not yet citizenship, for those currently in the United States illegally -- despite reports throughout his campaign for a “mass deportation.”

The senior administration official said that the president thinks it is “time to push for an immigration bill.”

Even still, plans to build a wall are underway, with the administration making its first steps to developing and implementing one of Trump’s hallmark campaign promises.

Trump told the Conservative Political Action Conference last Friday that construction will start “very soon” and is “way, way, way ahead of schedule.”

Nevertheless, a White House spokesperson said Tuesday the president is “open to having conversations” about fixing America’s immigration system, but the primary focus now is on “border control.”

The White House said Tuesday afternoon that immigration will be mentioned in Trump’s address to the joint session of Congress Tuesday night.

Bret Baier and Martha MacCallum anchor from Washington. Tune into Fox News Channel at 8:50pm ET for special coverage of President Trump’s first address to the Joint Session of Congress.