Washington: The United States said today it contributed USD 2.5 million for the demolition of the cooling tower of North Korea's key nuclear reactor as part of a denuclearisation effort.

A US official, speaking on condition of anonymity, confirmed the sum but could not verify reports that the total cost of the 30-metre tower's demolition was USD five million as claimed by the North Koreans.

The New York Times said in a report today that conservative hard-liners in Washington skeptical of the nuclear deal with North Korea felt the US contribution was too much.

TV footage showed the tower engulfed in a huge cloud of smoke as a landmark piece of the country's nuclear history collapsed in ruins.

"It was a significant and very important step," US State Department official Sung Kim told a reporter at the scene today.

"As I saw it, it was a complete demolition."

The cooling tower of the plutonium reactor in Yongbyon, 96 kilometres north of Pyongyang, was the most visible symbol of the communist state's decades-old pursuit of nuclear weapons.

Yongbyon had already been largely disabled under a six-party disarmament pact.

The demolition came a day after the North handed over a long-awaited declaration of its nuclear activities, which led to Washington partially lifting trade sanctions and taking steps to remove Pyongyang from a US terrorism blacklist.

Source : PTI