The president stressed that allowing the deal to expire would be a big mistakeRussia is prepared to continue abiding by the New START treaty on nuclear arms for one year even after it expires next February, Russian President Vladimir Putin has said. "Step by step, the system of Soviet-American and Russian-American agreements on nuclear missile and strategic defensive arms control was almost completely dismantled," Putin said. Putin noted that the New START treaty, signed in 2010 by Russia and the US, is the last remaining bilateral agreement limiting nuclear weapons. At the same time, Putin stressed that Moscow would implement this measure only if the US "follows suit and does not take steps that undermine or disrupt the existing balance of deterrence potential." If it is deemed that Washington is taking actions that undermine Moscow's efforts to maintain the status quo on strategic offensive arms, Russia will "respond accordingly," Putin said.