The 105-story Ryugyong Hotel, the tallest building in North Korea, towers above Pyongyang, on April 11, 2012. The hotel has been under construction (with numerous lengthy delays) since 1987. Parts of the pyramid are scheduled to open to the public as part of the centenary of Kim Il Sung's birth. (Reuters/Bobby Yip)

The 105-story Ryugyong Hotel, the tallest building in North Korea, towers above Pyongyang, on April 11, 2012. The hotel has been under construction (with numerous lengthy delays) since 1987. Parts of the pyramid are scheduled to open to the public as part of the centenary of Kim Il Sung's birth. (Reuters/Bobby Yip)

North Korean performers pause before singing at the Pyongyang indoor gymnasium to commemorate late president Kim Il Sung's 100th birthday in Pyongyang, on April 16, 2012. (AP Photo/Vincent Yu) #

Soldiers march past the podium during a military parade to celebrate the centenary of the birth of Kim Il Sung in Pyongyang, on April 15, 2012. (Reuters/Stringer) #

North Korean soldiers attend an official ceremony at the Kim Il Sung stadium in Pyongyang, on April 14, 2012. (Ed Jones/AFP/Getty Images) #

Thousands of North Koreans participate in a mass dance performance in Kim Il Sung Square to commemorate 100 years since the birth of the late leader Kim Il Sung, in Pyongyang, on April 16, 2012. (AP Photo/David Guttenfelder) #

A North Korean woman weeps while singing a song about North Korean leader Kim Jong Un at the end of a mass dance performance in Kim Il Sung Square in Pyongyang, on April 16, 2012. (AP Photo/David Guttenfelder) #

Pyongyang's Juche Tower before a fireworks display in Pyongyang on April 15, 2012. The tower rises 170 meters (560 ft) above the River Taedong. (Ed Jones/AFP/Getty Images) #

North Korean soldiers stand in formation during a military parade in honor of the 100th birthday of Kim Il Sung in Pyongyang, on April 15, 2012. (Ed Jones/AFP/Getty Images) #

Soldiers march in a military parade on the centenary of the birth of Kim Il Sung in Pyongyang, on April 15, 2012. (Reuters/KCNA) #

Soldiers march in a military parade in Pyongyang, on April 15, 2012. (Ed Jones/AFP/Getty Images) #

Members of the North Korean media wait in their position above Kim Il Sung square to cover celebrations of the 100th birth anniversary of Kim Il Sung, on April 16, 2012. (Ed Jones/AFP/Getty Images) #

North Korean soldiers march during a mass military parade in Pyongyang's Kim Il Sung Square, on Sunday, April 15, 2012. (AP Photo/David Guttenfelder) #

Soldiers march in formation during a military parade in Pyongyang, on April 15, 2012. (Ed Jones/AFP/Getty Images) #

North Korean military jets take part in a mass military parade in Pyongyang's Kim Il Sung Square, on Sunday, April 15, 2012. (AP Photo/Ng Han Guan) #

People watch a fireworks display in Pyongyang, on April 15, 2012. (Ed Jones/AFP/Getty Images) #

People wait to see a fireworks display in Pyongyang, on April 15, 2012. (Ed Jones/AFP/Getty Images) #

North Korean scientists work as a screen shows the Unha-3 (Milky Way 3) rocket on a launch pad at the West Sea Satellite Launch Site, on April 11, 2012. The rocket was launched shortly after, despite international condemnation -- and broke apart on its ascent. As a result of the launch, the United States canceled a proposed food aid deal with the North Koreans. (Reuters/Bobby Yip) #

A woman sits inside a booth on a street in Pyongyang, North Korea, on April 9, 2012. (AP Photo/Ng Han Guan) #

Rockets are carried by military vehicles during a military parade in Pyongyang, on April 15, 2012. (Reuters/KCNA) #

Soldiers applaud North Korean leader Kim Jong Un during a ceremony in Pyongyang, on April 14, 2012. (Reuters/Bobby Yip) #

Soldiers march in lockstep in a military parade in Pyongyang, on April 15, 2012. (Pedro Ugarte/AFP/Getty Images) #

North Korean leader Kim Jong Un waves during a military parade marking the centenary of the birth of his grandfather and the nation's founder Kim Il Sung, in Pyongyang, on April 15, 2012. (Pedro Ugarte/AFP/Getty Images) #

Soldiers march in a military parade in Pyongyang, on April 15, 2012. (Reuters/Stringer) #

A soldier decorated with military medals joins thousands of soldiers taking part in a ceremony in Pyongyang, on April 14, 2012. (Reuters/Bobby Yip) #

North Korean students ride down a water slide into a swimming pool at Kim Il Sung University in Pyongyang, on April 11, 2012. (Pedro Ugarte/AFP/Getty Images) #

Residential blocks in Pyongyang, on April 12, 2012. (Reuters/Bobby Yip) #

North Korean leader Kim Jong Un (center) attends the unveiling ceremony of two statues of former leaders Kim Il-Sung and Kim Jong-Il in Pyongyang, on April 13, 2012. (Pedro Ugarte/AFP/Getty Images) #

A North Korean woman looks up at balloons overhead at the end of an unveiling ceremony for statues of the late leaders Kim Il Sung and Kim Jong Il in Pyongyang, on April 13, 2012. (AP Photo/David Guttenfelder) #

A conductor waits for a train at Puhung subway station in Pyongyang, on April 14, 2012. Pyongyang's metro network was opened between 1969 and 1972 by former President Kim Il Sung, and is supposedly the deepest in the world with its track some 110 meters underground. (Ed Jones/AFP/Getty Images) #

Dancers perform during a gala show in Pyongyang, on April 16, 2012. (Reuters/Bobby Yip) #

Dancers stand in formation and sing in a gala show in Pyongyang, on April 16, 2012. The performance was part of the celebration on the centenary of the birth of Kim Il Sung. (Reuters/Bobby Yip) #

North Koreans walking on the street are framed by the windows of a bus in Pyongyang, on April 16, 2012. (AP Photo/Ng Han Guan) #

A traffic warden is seen from the window of a bus as he stands on an empty street before the Ryugyong Hotel in Pyongyang, on April 12, 2012. (Ed Jones/AFP/Getty Images) #

North Korean men look up as a plane flies overhead in Pyongyang, North Korea, on April 12, 2012. The press bus took a wrong turn this day, and suddenly, everything changed in the official showcase of North Korean achievement. The drivers quickly backed up the three buses in the narrow deeply potholed streets and headed toward the intended destination: a spotlessly clean, brightly-lit, extensively marbled and nearly empty building that preserves digital music recordings and makes DVDs. (AP Photo/Ng Han Guan) #

A portrait of North Korea founder Kim Il Sung is shown during a concert in Pyongyang, on April 16, 2012. (Reuters/Bobby Yip) #

Soldiers run into a stadium to join a ceremony in Pyongyang, on April 14, 2012. (Reuters/Bobby Yip) #

A North Korean choir sings during a concert in Pyongyang, on April 16, 2012 to commemorate 100 years since the birth of Kim Il Sung. (AP Photo/David Guttenfelder) #

A dancer dressed as a soldier takes part in a gala show in Pyongyang, on April 16, 2012. (Reuters/Bobby Yip) #

North Koreans watch a theater performance during celebrations to mark the 100th birth anniversary of Kim Il Sung, in Pyongyang, on April 16, 2012. (Pedro Ugarte/AFP/Getty Images) #

North Koreans walk past a light box featuring Kimjongilia, a flower named after the late leader Kim Jong Il, during a flower show in Pyongyang, on April 17, 2012. (AP Photo/Vincent Yu) #

A North Korean soldier stands guard at the space center in Pyongyang, on April 11, 2012. (Pedro Ugarte/AFP/Getty Images) #

Military members attend a mass meeting called by North Korea's ruling party in a stadium in Pyongyang, on April 14, 2012. (AP Photo/Ng Han Guan) #