Bush ups ante on Iran, N Korea

In back-to-back meetings with the leaders of China, Japan and South Korea here Saturday morning, Bush urged each to draw North Korea back into six-nation negotiations. And in a speech later, he issued a direct challenge to North Korea’s reclusive leader that echoed President Reagan’s demand in 1987 for the dismantling of the Berlin Wall.

After the meetings, Bush said he was convinced ‘‘that the will is strong, that the effort is united and the message is clear to Mr. Kim Jong-il: Get rid of your nuclear weapons programmes.’’ His aides played down informal intelligence estimates that the country has already produced enough plutonium in the past two years to manufacture six additional nuclear weapons.

Bush’s efforts here underscored his determination to reverse two nuclear projects that appear to have made significant progress while American attention has been focused on Iraq.

In Iran’s case, he is clearly sceptical about a European-led effort to suspend the country’s manufacture of nuclear material, and in North Korea he is facing a country that has defied every previous effort he has made to force it to dismantle what it has already built.

The American president told reporters on Saturday that he was ‘‘concerned about reports’’ that said Iran appeared ‘‘willing to speed up processing of materials that could lead to a nuclear weapon’’.

Diplomats had said the day before that Iran had told the International Atomic Energy Agency that it was racing to produce uranium hexafluoride, a gas that can be enriched into bomb fuel, before it begins to observe the temporary suspension of nuclear activity that it negotiated with the Europeans.

The American president’s comments marked the second time this week that the administration has accused Iran of heading quickly toward nuclear weapons, despite its protestations to the contrary.

Following Bush’s assertion on Saturday that Iran had accelerated its uranium enrichment, Secretary of State Colin L. Powell appeared at a news conference here with Foreign Minister Ignacio Walker Prieto of Chile and was asked to provide details to back that up but declined to do so. He said that in the past four years, as a result of American cries of alarm about Iran’s intentions, the international community was now ‘‘as concerned as we are’’ about the problem.