July 6 (Bloomberg) -- Presidents Barack Obama and Dmitry Medvedev agreed to slash their nuclear arsenals and cooperate on military action in Afghanistan as the U.S. and Russia seek to “reset” ties at a Moscow summit.

The two leaders called for a reduction of nuclear warheads by as much as a third from current limits in a Kremlin meeting. Russia also agreed to allow the transit of U.S. arms shipments to troops fighting the Taliban in Afghanistan.

“We resolved to reset U.S.-Russian relations,” Obama told reporters, referring to his first meeting with Medvedev in April. “Today, after less than six months of collaboration, we have done exactly that.”

Obama arrived in the Russian capital today after pledging to refresh relations that reached a post-Cold War low under George W. Bush because of disagreements over the eastward expansion of the North Atlantic Treaty Organization, a proposed U.S. missile shield in Europe and Russia’s war with Georgia.

The agreement on nuclear targets sets the course for negotiators to replace the 1991 Strategic Arms Reduction Treaty, which expires in December. The two sides also agreed to form a commission headed by Secretary of State Hillary Clinton and Foreign Minister Sergei Lavrov to keep open the lines of communication.

Nuclear Security Summit

The U.S. intends to host a global nuclear security summit next year, Obama said, adding that a subsequent meeting could be held in Russia. The two countries, which hold 95 percent of the world’s atomic weapons, must lead by example if they expect other countries to collaborate on nuclear non-proliferation, the U.S. president said.

“This kind of outcome was the best we could expect,” Pavel Podvig, a researcher at the Center for International Security and Cooperation at Stanford University, said by phone. “The key thing is they put some numbers on paper.”

The two presidents agreed to a reduction of their nuclear arsenals to between 1,500 and 1,675 warheads and between 500 and 1,100 delivery vehicles. Current limits allow a maximum of 2,200 warheads and 1,600 launch vehicles.

The U.S. will return to the issue of the missile shield, which Russia says would hurt its defense posture, when it completes its review of Bush-era plans, Obama said. Differences with Russia on missile defense can be reconciled, he added.

Supply Route

Russia’s agreement to allow the transit of military personnel and materiel to U.S. troops in Afghanistan helps Obama redouble the American war effort as Pakistan becomes increasingly unreliable as a supply route. Medvedev began allowing shipments of non-lethal cargoes bound for Afghanistan to pass via its territory in March.

The two leaders praised each other, with Medvedev calling the talks “open and sincere” and Obama characterizing his Russian counterpart as “professional and straightforward.”

Obama said he and Medvedev discussed issues where the U.S. and Russian positions diverge, including the situation in Georgia. Nobody has an interest in renewing the conflict that saw Russia recognize the Georgian breakaway regions of South Ossetia and Abkhazia after a five-day war, he said.

“President Medvedev and I are committed to leaving behind the suspicion and rivalry of the past so we can advance the interests we hold in common,” Obama said.

A new commission headed by Clinton and Lavrov will see to it that relations don’t deteriorate again, the U.S. president said. The new forum is reminiscent of the so-called Gore- Chernomyrdin commission, which managed relations between the governments of Bill Clinton and Boris Yeltsin.

Tomorrow morning, Obama will meet Medvedev’s predecessor and mentor, Prime Minister Vladimir Putin, for a breakfast meeting. The U.S. president will then deliver a commencement speech to students of the New Economic School and talk with former Soviet leader Mikhail Gorbachev, business and opposition leaders.

To contact the reporters on this story: Lucian Kim in Moscow at lkim3@bloomberg.net; Hans Nichols in Moscow at hnichols2@bloomberg.net; Roger Runningen in Moscow at rrunningen@bloomberg.net

Last Updated: July 6, 2009 13:47 EDT