The row has heightened tensions on the peninsula

It has been angered by President Bush's accusation that Pyongyang was part of an "axis of evil" producing weapons of mass destruction.

This annoyance was compounded by Washington's decision to withhold this year's certification that North Korea is keeping its side of the Agreed Framework.

It has systematically refused to allow International Atomic Energy Agency (IAEA) inspectors into its nuclear facility at the Yongbyon research base north of the capital.

Delayed

Pyongyang has justified its refusals by pointing out that the reactors are way behind schedule.

They were originally expected to have been completed next year, but now construction is not expected to even begin until August.

Another issue is the different interpretations of the inspections' timing.

According to the Framework, North Korea should be fully compliant with IAEA safeguards when "a significant proportion" of the project is completed.

The builders say that will be around May 2005, and given the inspections will take at least three years, this means that North Korea should start admitting inspectors now.

But Pyongyang believes that they should only allow the inspections to start, rather than finish, by that date.

The head of the Non-proliferation Policy Education Centre in Washington, a critic of the Agreed Framework, has warned that even when the new reactors are completed they may not be tamper-proof.

"These reactors are like all reactors, They have the potential to make weapons. So you might end up supplying the worst nuclear violator with the means to acquire the very weapons we're trying to prevent it acquiring," Henry Sokolski told the Far Eastern Economic Review.