MOSCOW - A top U.S. envoy today dismissed claims that Russia was the United States' greatest adversary and instead painted Moscow as a complex but essential partner on a range of issues.

"Russia is not an easy partner, there's no question about that, but at the same time I think that the facts on the ground prove out that this relationship has been beneficial to the United States of America," Rose Gottemoeller, the Acting Under Secretary for Arms Control and International Security, said in an interview with ABC News on Friday.

Gottemoeller was the lead American negotiator with Russia over a landmark nuclear weapons reduction treaty known as New START, which entered into force last year. She cited the implementation of that agreement, as well as an effort to hunt down shoulder-fired rockets in Libya and the establishment of NATO supply routes for the war in Afghanistan as examples of critical cooperation.

"We can't lose sight of that," she stressed, arguing that US-Russia relations had improved since President Obama took office.

Gottemoeller's comments came after Republican presidential hopeful Mitt Romney ignited a fierce debate this week over Russia's role in the world and how the United States deals with it after he called Moscow "America's number one geopolitical foe."

Romney accused the White House of kowtowing to the Kremlin after President Barack Obama was caught on an open microphone earlier in the day asking Russian President Dmitri Medvedev to withhold criticism of a US-led missile defense shield in Eastern Europe until after the November election. President Obama was heard asking the Russian leader for "space" and said he would have more "flexibility" on missile defense after the election.

During the interview after a speech to students in Moscow on Friday, Gottemoeller denied President Obama's remarks meant there would be no progress on missile defense until the end of the year and said he was not referring to any sort of secret concession that would only be revealed after the election.

President Obama explained his comments saying it was a political reality that little progress is likely during a politically charged election year.

Gottemoeller was also skeptical of a breakthrough this year, but believed she and her Russian counterparts will make progress in the interim until political leaders on both sides are ready to strike a deal.

"We'll get through this campaign season," she said. "We just need to get through it and in the meantime keep doing our practical work in every way we can, which will be my intention."

Russia has been going through its own heated campaign season this year, which has led to higher than normal levels of anti-Americanism in political discourse. Prime Minister Vladimir Putin, who earlier this month won another term as President, accused the U.S. of paying protestors to take to the streets against him. It was an effort, experts say, to discredit the massive rallies that shook his image of invincibility.

For much the same reason, analysts say, the Kremlin has stirred suspicions about the American plan for a missile defense shield, which U.S. officials insist is designed to defend Europe against an attack from Iran. Russian officials claim it is aimed at their arsenal.

Gottemoeller dismissed the Cold War-era suspicions as political tools in Russia.

"I put that down a lot to the kind of political requirements of the campaigning season here," she said.

She said some of her Russian counterparts admit the expressed concerns about the missile defense shield are for domestic politics, while others do not yet understand the system's capabilities.

"They tell me point-blank they recognize that at a technical level there is no threat to Russian strategic offensive forces from the technologies that we are proposing. Other people simply are not such technical experts and they do not have a full grasp of the technical capabilities and they are concerned about this at both a political level and a technical level," she said.

In his criticism of Russia, Romney cited its support for what he called "the world's worst actors." He pointed to the Kremlin's backing of Syrian President Bashar al-Assad, who has led a bloody crackdown on a protest movement that has called on him to step down. Russia has blocked tough measures against Syria at the United Nations Security Council, which the U.S. and its allies hoped would end the violence and help remove Assad from power.

In the interview today, Gottemoeller admitted that Russia has not been helpful with regard to Syria.

"Its' obvious we and Moscow don't agree on how to handle the Assad regime at the present time," she said.

Despite the politics of the US-Russian relationship in both countries, Gottemoeller said her challenge is to continue working with her counterparts until the political leaders are ready to strike a deal.

At the end of her speech a student asked Gottemoeller how to prevent politics from derailing diplomacy.

"It's impossible," she said with a smile. "Welcome to my world."