Under the plan, the United States would place part of its defense shield in Poland and the Czech Republic.
Obering, together with a U.S. delegation, met with officials at the Defense Ministry, Ukraine's Security Council, and president's office.
No Ukraine Plans
Speaking at a news conference in Kyiv, Obering vowed his country had no plans to deploy other parts of the shield in Ukraine.
In response to a question by RFE/RL's Ukrainian Service, Obering rejected reports that the United States sought to place a radar in one of the Caucasus nations.
Obering reiterated that the system is designed to protect Europe from potential missile attacks by "rogue nations" such as Iran and North Korea.
He also said that Ukraine has nothing to fear from a potential missile intercept over Ukraine. In that case, he said, the entire warhead would be destroyed and no debris would fall over the country.
Ukraine, which neighbors Poland, is still divided on the U.S. missile plans.
Some, like Western-leaning President Viktor Yushchenko, have given the plan a cautious welcome. Yushchenko says it could help Europe create a unified defense system.
Others are worried about its impact. The Moscow-backed Prime Minister Viktor Yanukovych has cautioned that Ukraine, by allowing the U.S. defense system to be set up on its doorstep, could damage relations with its neighbors.
Ukraine's government has yet to give a formal response.
The U.S. plan has sparked an angry reaction from Russia, with Russian military officials warning Poland and the Czech Republic that hosting the U.S. defense system on their soil could make them targets of a Russian missile strike.
Obering said Russia's anger is unfounded.
"Of course, we had a reaction from the Russians that was unexpected and they referred to changing the strategic balance between the United States and Russia. We disagree with this, respectfully. We're talking about no more than 10 interceptors and they would have no effect against the hundreds of missiles or thousands of warheads that the Russians have," Obering said.
While Obering today was able to address some of the worries caused by the Pentagon's missile initiative, his visit to Kyiv also gave him the opportunity to witness firsthand Ukrainian hostility to the plan.
Demonstrators disputed his press conference, chanting "Yankee go home!" and holding a banner reading "Ukraine is against NATO."
Obering's Ukrainian visit is part of an information campaign around Europe about the U.S. missile shield.
Obering travels to Berlin on March 15 and then Paris to discuss the project with senior officials of both countries.
In Brussels today, a NATO spokesman said the alliance will "in the coming weeks" begin talks on the missile defense system.
The spokesman, James Appathurai, said, however, that NATO does not want to "interfere" with current U.S. plans to build interceptor and radar sites in Poland and the Czech Republic, but to "complement" them.
"The challenge is not, certainly from NATO's view, to -- as I say -- interfere with or slow down the U.S. bilateral discussions with allies. The challenge is, a), to get a common view [among the allies], and, b), to see how we can potentially complement this initiative," Appathurai said.
Appathurai said that NATO wants to ensure the same level of protection for all its member states.