Addressing a symposium marking the 20th anniversary of the Nunn-Lugar Cooperative Threat Reduction Program, Obama praised the “extraordinary progress” achieved under the pact, which has resulted in the deactivation of 7,600 nuclear warheads.

Obama appealed to Russia to maintain joint efforts to prevent terrorists from getting their hands on nuclear material.

“Nuclear terrorism remains one of the greatest threats to global security,” Obama said. “Let’s work with Russia as an equal partner.”

The Threat Reduction Program was initiated under a 1992 law sponsored by Sen. Richard Lugar from the US state of Indiana and former Sen. Sam Nunn from the state of Georgia.

Russia announced this past October that it would not renew the pact when it expires next June. The announcement came at a time of increased scrutiny by Russia of US activities in the country. Just a week before that, Russia halted the United States Agency for International Development from working in the country earlier this month.

Russian Foreign Ministry spokesman Alexander Lukashevich said in October that the Nunn-Lugar agreement was in need of an overhaul, though he did not provide details.

“Our American partners know that their proposal is at odds with our ideas about the forms and basis for building further cooperation in that area,” Lukashevich said at the time.

“A more modern legal framework” is needed for such interaction, Lukashevich added.