Bernie Sanders is increasing the pressure on the White House administration over the immigration enforcement initiatives taking fresh aim at the controversial program only days prior to the presidential contest for Democrats in Nevada.

Sanders through a letter he wrote with Raul Grijalva a Democrat from Arizona, criticizes the Priority Enforcement Program that is in place to help immigrations authorities at the federal level to work with law enforcement at the local level to identify immigrants who should face deportation from the U.S.

The initiative is at the center of the executive actions by President Barack Obama unveiled on immigration in November of 2014, though it has been getting much less attention than his actions granting work permits to possibly millions of undocumented immigrants in the U.S. illegally.

However, the PEP that was meant to replace the Secure Communities initiative, which is quite controversial, has attracted criticism from immigration advocates and liberals who have argued it entangles local strategies of policing wrongly with immigration enforcement.

In his presidential nomination bid for the Democrats, Sanders holds an aggressive liberal stance regarding immigration and has hired a number of well known Hispanic activists to help his campaign.

Sanders vowed to expand the proposal of Obama to grant the work permits that are currently entangled in court.

As the Nevada caucuses approach, the positions of Sanders on immigration will likely come more into focus as Nevada has a large population of Hispanic voters.

Grijalva is just one of two Capitol Hill Democrats who have endorsed the Vermont Senator over his biggest challenger Hillary Clinton. Keith Ellison a Democrat in the House from Minnesota is the other, who with Grijalva is the co-chair of the Congressional Progressive Caucus.

Sanders said there is more safety when law enforcement agencies at the local level have the ability to work and have trust with the immigrant communities.

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