CNN

Cohen said Obama made the right move.

WASHINGTON (CNN) – Former Secretary of Defense William Cohen told CNN President Obama’s decision to reach out to Russian President Dmitry Medvedev was the right one.

His comments Tuesday came as the administration continued to deny reports a letter from Obama to Medvedev - which Cohen said seemed to have been “prematurely leaked” - contained any offer to end U.S. plans for a missile defense system if Russia agreed to help keep Iran from acquiring nuclear weapons.

The former Clinton official conceded reaching agreement could prove too tough. “It may not be possible to get Russia on board,” Cohen said of U.S. efforts to deal with Iran’s weapons program. “If they're not, then the other issue becomes whether or not a military option is wise, advisable, or simply off the table. But I think if there's going to be a diplomatic solution, Russia's going to have to be involved with it to make it successful.”

He said that if Iran cannot divide the UN Security Council with its dependence on Russian and Chinese support, “the pressure that can be brought on under those circumstances can be quite intense.”

Cohen described Obama’s letter to Medvedev as an attempt to set up a dialogue to bring a thaw to the recently icy relations between the two nations. “I think there has been a level of distrust [on the part of the Russians with the United States], and what President Obama seeks to do and I think we want to encourage him to see if there can’t be a method of establishing a working relationship with the Russians,” he told CNN. “I think it’s very important for global security that we have a good relationship with Russia and a good relationship with China, and to that extent I commend President Obama for reaching out and seeing whether we can do that.”

On Tuesday, Medvedev praised the administration’s outreach efforts, though he downplayed any chance of Russian cooperation with the United States on addressing Iran’s weapons prgram.

Cohen said Tuesday he continues to support a missile defense system, like the one currently in place in the Czech Republic and Poland, to defend against possible strikes by nations other than Russia.

“I tend to be a strong supporter of having a missile defense system for the United States, to hedge against a miscalculation or mistake or even an accidental launch, “ said Cohen.