Senate talks on border resume as Blinken heads to Mexico

Bipartisan negotiations resume Wednesday between senators on a potential border security package, a source familiar confirms.

ABC News is told the conversations will be held remotely as the Senate is out on recess for the holiday and is not expected to return until Jan. 8.

Before leaving town last week, principal Senate negotiators signaled they were making "progress" on a potential deal and that they would continue discussing it during the recess.

Democrat Sen. Chris Murphy, GOP Sen. James Lankford and Arizona independent Sen. Kyrsten Sinema -- the trio leading the talks -- had been huddling for weeks to try to find a way forward on changes to immigration and border security.

Details on what could be in a potential border security package are still slim, but the main areas of discussion include: toughening asylum protocols for migrants arriving at the U.S.-Mexico border, bolstering border enforcement with more personnel and high-tech systems and deterring migrants from making the journey to the US in the first place.

The senators say they are trying to ensure that migrants who have a credible claim to asylum can safely apply, but that officials can also quickly turn away those who don’t qualify. The goal, senators have said, is to create a more orderly, efficient asylum system that reduces chaos at the border.

Republicans have insisted that a bipartisan compromise on immigration and border security policy is necessary to advance additional funding for Ukraine, Israel and Taiwan.

Secretary of State Antony Blinken and Secretary of Homeland Security Alejandro Mayorkas traveled to Mexico City on Wednesday to meet with the country’s president, Andrés Manuel López Obrador -- better known as AMLO -- and their Mexican counterparts behind closed doors, as both countries struggle to address urgent issues posed by surging irregular migration. The two U.S. Cabinet members are scheduled to return to Washington later on Wednesday.

A source familiar with U.S.’ goals for the visit said earlier that the officials were hoping to find ways to convince Mexico to do more to ramp up immigration enforcement at its own southern border, commit more resources to operating its side of legal crossings (especially those that have been temporarily closed in recent weeks), restart deportations and transfers within the country that were suspended earlier in the month, and discuss incentives aimed at encouraging migrants to stay in Mexico rather than cross into the U.S.

AMLO has publicly said he wants more U.S. aid flow to Mexico and the broader region, including to Venezuela and Cuba.

President Joe Biden has previously said he is willing to make “significant compromises” on immigration policy to secure an aid deal for Ukraine in its war against Russia.

The urgent meeting comes as a caravan of an estimated 6,000 migrants makes its way to the U.S. border.

ABC News' Shannon Crawford contributed to this report.