Sen. Jeff SessionsJefferson (Jeff) Beauregard SessionsMcCabe to sue Trump admin for defamation, wrongful termination Trump pressed Sessions to fire FBI agents who sent anti-Trump texts: report The Hill's Morning Report: Inside the Comey memos MORE (R-Ala.) blamed President Obama for the influx of unaccompanied minors trying to cross the border illegally.

“The crisis at our border continues to go unabated,” Sessions said on the Senate floor Monday. “No nation in the world that I’m aware of maintains open borders.”

Sessions said instead of asking for $2 billion from Congress to address the issue, Obama should enforce existing immigration laws.

“The problem is that we have laws and Congress has established laws and the president wanted to change those laws and Congress made a decision and that decision was not to change those laws,” Sessions said. “[Obama] has the highest duty to ensure that the laws of the United States are faithfully executed."

Republicans have blamed the detention of thousands of unaccompanied children from Honduras, El Salvador and Guatemala into the U.S. on Obama’s decision to defer the deportation of illegal immigrant children who were brought to the United States by their parents, also known as Dreamers. New children entering the country would not be eligible for deferred action.

"This is the direct action that had led to this crisis today," Sessions said. "It is a direct affront to the rule of law. ... And it's just wrong."

Obama has called on House Republicans to consider a bipartisan Senate bill. The Senate passed a comprehensive immigration reform bill last year, which would provide a pathway to citizenship for illegal immigrants within the country, increase student and work visas and spend more on border security.