Members of the US congress are urging that the Department of States "reassess" aspects of its security cooperation with Mexico amid mounting concerns about human rights.

In a letter sent to Secretary of State Anthony Blinken on Thursday, the members of congress said that the Biden administration must "develop a strategy" for the entry of tens of thousands of migrants currently waiting in Mexico to continue their US immigration proceedings or request asylum.

"We encourage coordination with the Mexican government and international organizations and consultation with civil society organizations to ensure that during any continued wait in Mexico, asylum seekers have access to water, food, healthcare, shelter and protection from crime," the letter said. 

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The matter is urgent, the letter added, as a result of ongoing and frequent incidents of violence against migrants in Mexico. In January, for example, Mexican authorities discovered the remains of 19 people - mostly Guatemalan citizens - in Tamaulipas.

More broadly, the members of congress urged Blinken to help Mexico address it's crime rate, which has seen approximately 35,000 people murdered every year, as well as 30 human rights defenders and journalists killed in 2020 alone. More than 80,000 people have disappeared since 2006.

We encourage coordination with the Mexican government and international organizations and consultation with civil society organizations to ensure that during any continued wait in Mexico, asylum seekers have access to water, food, healthcare, shelter and protection from crime

"In this context, we encourage you to work with the Mexican government to address the near-total levels of impunity that enable criminal groups and state agents to perpetuate serious crimes and human rights abuses," the letter said.

We encourage you to explore ways to deepen US-Mexico cooperation to improve investigations and increase the percentage of successfully prosecuted cases, including of corruption crimes and collusion between state actors and criminal groups

As a result of the worsening security situation in Mexico, the letter said the US should "reassess" aspects of security assistance to Mexico, including the focus on arresting cartel kingpins and the Mexican government's growing reliance on the military and National Guard to combat crime and enforce immigration policies.

"We encourage you to explore ways to encourage his administration to follow through on its previously stated commitment to withdraw the military from policing by 2024," the letter said. "It will be critical to deepen US efforts to help ensure that civilian police can work in an effective and rights-respecting way and establish internal and external accountability mechanisms."

Lastly, the letter called on Blinken to do more to support civil society and human rights advocates.

"We have been encouraged by President Lopez Obrador's statements targeting human rights defenders and journalist and encourage you to consistently raise these concerns with Mexican authorities," it said.

In addition to helping Mexico strengthen its protection system for journalists and human rights defenders, the letter calls on the State Department to help strengthen Mexico's forensic capacity and support investigations.

"We encourage you to meet with human rights defenders and journalists to hear their concerns and learn about their important work," the letter said. "We are confident that you will work to ensure that human rights are at the heart of our country's policy toward Mexico. We will make every effort to support that goal."

The letter was signed by 19 members of congress, including California's Alan Lowenthal, Texas' Joaquin Castro, Jesus ‘Chuy' Garcia from Illinois and Minnesota's Ilhan Omar.

Earlier this week, US President Joe Biden held a virtual meeting with Mexican President Andrés Manuel López Obrador.

Security issues, however, were largely absent from the discussion, with a joint declaration only briefly mentioning a commitment from both countries to "improve law enforcement".

Cooperation between the two countries has been strained following a Mexican measure to curtail security cooperation following the controversial arrest of former Mexican Defense Minister General Salvador Cienfuegos in October.