The United States has welcomed North Korea's nuclear declaration and promised steps to take the North off Washington’s list of state sponsors of terrorism and ease some trade sanctions.

US president George W Bush.

"We welcome the ..."

According to China's Foreign Ministry, North Korean ambassador to China Choe Jin Su submitted the declaration to Wu Dawei, China's top negotiator on the Korean Peninsular nuclear issue.

On Friday, North Korea was expected to blow up the cooling tower at its Yongbyon nuclear complex in front of international television cameras.

The tower's destruction is regarded as a symbolic act designed to show Pyongyang's intent to abandon its nuclear ambitions.

It's also seen as a potential breakthrough in the impasse that has stalled the six-party nuclear negotiations for months.

Under an agreement reached at the six-party talks in Beijing last October, North Korea agreed to abandon all nuclear weapons and programs and declare all its nuclear programs and facilities by the end of 2007, in exchange for diplomatic and economic incentives.

But Washington said Pyongyang missed the deadline despite reported progress in its nuclear disablement and declaration.

The six-party talks have since been stalled.