The breakthrough announced yesterday is intended to salvage a faltering disarmament accord before President George W. Bush leaves office in January.

'Every single element of verification that we sought going in is part of this package,' State Department spokesman Sean McCormack said at a rare weekend briefing.

North Korea will allow atomic experts to take samples and conduct forensic tests at all of its declared nuclear facilities and undeclared sites on mutual consent.

The North will permit experts to verify that it has told the truth about transfers of nuclear technology and a suspected uranium programme.

'Verifying North Korea's nuclear proliferation will be a serious challenge. This is the most secret and opaque regime in the entire world,' said Ms Patricia McNerney, assistant secretary for international security and non-proliferation.

North Korea was added to the terror list in 1988 following the bombing by its agents of a Korean Airlines plane on Nov 29, 1987, which killed all 115 on board.

The State Department says the North is not known to have sponsored any terrorist acts since that bombing.

The decision to strike Pyongyang off the blacklist followed days of intense debate in Washington and consultations with US negotiating partners China, South Korea, Russia and Japan.

Tokyo had baulked at the move because North Korea has not resolved issues related to its abduction of Japanese citizens.

'The key principle of the six-party talks is that any agreement must be agreed upon and in essence guaranteed. The next is to go to the six and have this formalised,' Mr McCormack said.

President Bush yesterday vowed to press Japan's case over the hostage issue.

The removal of North Korea from the blacklist was immediately criticised by some US congressmen, who said it sends a bad signal to other US adversaries, notably Iran.

But US officials stressed that the North would be placed back on the blacklist - and suffer the sanctions that go with it - if it fails to comply with the verification plan.

Shortly before the announcement, North Korea released pictures of its leader Kim Jong Il for the first time in nearly two months, showing him looking generally well despite reports that he recently underwent brain surgery.

The photos were taken during a visit to a military unit and shown on Pyongyang's Korean Central Television. Mr Kim, 66, appeared healthy in the images, though it was unclear when they were taken.

Separately, the US and India signed an accord earlier yesterday that allows American businesses to sell nuclear fuel, technology and reactors to India, reversing a three-decade ban on atomic trade with the fast-growing nuclear-armed Asian power.

'This is truly a historic occasion,' US Secretary of State Condoleezza Rice said at the ceremony at the State Department.

The two countries 'now stand as equals, closer together than ever before', she said with India's Foreign Minister Pranab Mukherjee by her side.

AP, AFP, Reuters