Updated

With help from the U.S., the Czech Republic has eliminated its stockpile of highly enriched uranium, becoming the 10th country to remove all such material since President Barack Obama began pushing to rid the world of nuclear weapons, the White House said Friday.

The announcement came on the fourth anniversary of a speech Obama delivered in the Czech capital of Prague shortly after taking office in 2009. He declared nuclear terrorism the world's greatest threat and called on other countries to secure their stockpiles of nuclear material.

The United States and its international partners helped remove 68 kilograms of highly enriched uranium, about 150 pounds, from the Czech Republic, said National Security Council spokeswoman Caitlin Hayden. The material, enough for two nuclear weapons, was sent by secure transport to Russia to be converted into low-enriched uranium for use in nuclear power reactors, she said.

Unlike highly enriched uranium, low-enriched uranium cannot be used to make a nuclear weapon.

More than 3,000 pounds of highly enriched uranium and plutonium, enough for dozens of nuclear weapons, have been removed since Obama's speech in Prague on April 5, 2009, according to the U.S. National Nuclear Security Administration, an agency of the Department of Energy.

"Today we can say without a doubt that the world is safer from nuclear terrorism than it was four years ago," said Neile Miller, the agency's acting administrator.

The hardest part of building an atomic bomb, according to arms control experts, is acquiring the weapons-grade uranium or plutonium needed for the bomb's explosive core. Locking up or eliminating this material is crucial to preventing nuclear-armed terror.

The U.S. is also working with Uzbekistan, Hungary and Vietnam to remove weapons-grade material from those countries by the end of the year.

In his speech four years ago, Obama called nuclear weapons "the most dangerous legacy of the Cold War."

"Some argue that the spread of these weapons cannot be checked, that we are destined to live in a world where more nations and more people possess the ultimate tools of destruction," he said. "This fatalism is a deadly adversary. For if we believe that the spread of nuclear weapons is inevitable, then we are admitting to ourselves that the use of nuclear weapons is inevitable."

Besides the Czech Republic, other countries that have removed highly enriched uranium since Obama's speech are Romania, Libya, Turkey, Chile, Serbia, Austria, Mexico, Ukraine and Taiwan.

The operation in the Czech Republic was carried out by the National Nuclear Security Administration, the Czech Republic's Nuclear Research Institute, Russia's State Corporation for Atomic Energy and the International Atomic Energy Agency.

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Online:

U.S. National Nuclear Security Administration: http://nnsa.energy.gov/

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