BERLIN — US President Barack Obama used a speech in Berlin on Wednesday to call on Russia to revive the push for a world without nuclear arms by agreeing to target further reductions of up to one third of deployed nuclear weapons.



Meanwhile, Russian deputy PM mocks Obama’s nuclear cuts proposal. Speaking in Berlin where John F. Kennedy and Ronald Reagan gave rousing Cold War speeches, Obama urged Russia to help build on the “New START” treaty that requires both countries to cut stockpiles of deployed nuclear weapons to 1,550 each by 2018.



“After a comprehensive review I have determined that we can ensure the security of America and our allies, and maintain a strong and credible strategic deterrent, while reducing our deployed strategic nuclear weapons by up to one third,” he said.



“I intend to seek negotiated cuts with Russia to move beyond Cold War nuclear postures,” Obama said at the Brandenburg Gate, which once stood alongside the Berlin Wall that divided the communist east and the capitalist west.



Obama’s vision of a “world without nuclear weapons” set out in a speech in Prague in 2009, three months into his presidency, earned him the Nobel Peace Prize. But his mixed results so far have fueled criticism that the prize may have been premature.



Experts said reducing the nuclear arsenal makes strategic and economic sense. But Mark Fitzpatrick at the International Institute for Strategic Studies said Obama faces major obstacles “including a recalcitrant Russia and a reluctant Senate.”



President Vladimir Putin, speaking in St. Petersburg minutes before Obama’s speech, made no direct comment but voiced concern about US missile defenses and high-precision weapons.



Moscow sees nuclear deterrents as the safeguard of national security. It is worried about the West’s superior conventional weapons and NATO plans for a missile defense system in Europe.



“High-precision conventional weapons systems are being actively developed ... States possessing such weapons strongly increase their offensive potential,” said Putin.



The chief of the Russian military’s general staff appears reluctant to negotiate a new nuclear deal and Russian foreign policy expert Fyodor Lukyanov described Obama’s desire to “go to zero globally” as totally unacceptable in Russia.



Russia’s deputy prime minister poured cold water Wednesday on President Obama’s nuclear weapon cuts proposal, saying it could not be taken seriously while the United States is developing its missile defense system. “How can we take seriously this idea about cuts in strategic nuclear potential while the United States is developing its” capabilities to intercept Russia’s weapons, Dmitry Rogozin asked.



“Clearly, (Russia’s) political leadership cannot take these assurances seriously,” said Rogozin, who oversees the defense sector and the nuclear industry, according to the state-owned Itar-TASS news agency.



“The offense arms race leads to a defense arms race and vice versa,” he said, speaking after a government meeting in Saint Petersburg that focused on Russia’s defense sector. — Agencies