US urges penalties to deter atom treaty walkouts

VIENNA, May 9 (Reuters) The United States and EU allies said today North Korea and Iran posed the most acute threat to the nuclear Non-Proliferation Treaty and Washington called for new measures to deter withdrawals from the pact.

North Korea pulled out of the NPT in 2003 and exploded a nuclear device last year while the UN has imposed sanctions on Iran for suspected noncompliance with NPT safeguards meant to prevent the spread of atomic bomb technology.

Western powers zeroed in on Tehran and Pyongyang at a meeting in Vienna of 130 NPT member nations to assess ways of reinforcing the fraying treaty.

The two-week proceedings, due to end on Friday, were stalled for a week by Iranian objections to an agenda it feared would single it out while glossing over other treaty issues.

Tehran accepted a compromise on Tuesday in which nuclear-armed states agreed to allow discussion of plans to modernise their arsenals despite commitments to phase them out.

When debate shifted to non-proliferation today, Western delegations dwelled on Iran and North Korea as symbols of what ails the NPT and called for tough countermeasures.

But developing nations' delegates said only total nuclear disarmament would assure respect by all for the NPT.

Washington said the conduct of Iran and North Korea highlighted the treaty's weaknesses.

It said North Korea's detonation of what ''it had been developing for years while a member in bad faith of the NPT'', and hints from Tehran it could quit the treaty too if sanctions intensified, underlined a need for the accord to be revised.

US delegation chief Christopher Ford called for NPT dropouts to be banned from importing further nuclear materials, to be required to return goods obtained earlier ostensibly for peaceful ends, and face branding by the U.N. Security Council as a threat to peace that warranted punishment.

''HOLLOW'' TREATY? ''It's important to make withdrawal such (as North Korea's) unattractive before other violators are tempted to follow such a course ... (Otherwise), treaties such as the NPT could quickly become dangerously hollow formalisms,'' Ford said.

After a second batch of sanctions were levelled on Iran in March for its refusal to stop enriching uranium, Tehran said it still intended to stay in the NPT and allow continued inspections by the UN nuclear watchdog agency.

But powerful Iranian hardline factions have said Tehran should walk out of the NPT if it is only going to get punished.

They say it is pursuing its right to what they insist is a civilian nuclear energy industry within the terms of the treaty.

Western powers suspect otherwise, as Iran did not report sensitive nuclear research to the International Atomic Energy Agency for almost 20 years and has since dodged IAEA inquiries aimed at verifying its activity is wholly peaceful.

The NPT binds members without nuclear weapons not to acquire them, guarantees the right of all members to peaceful nuclear energy, and obliges the original five nuclear powers from the post-World War Two era to dismantle arsenals in stages.

There was broad consensus at the meeting for a nuclear arms-free zone in the unstable West Asia, which would entail Israel dismantling its undeclared nuclear arsenal.

But the idea will be only lip service without normal ties between Israel and its Arab neighbours and Iran, analysts say.

''It's not politically feasible or realistic before a peace settlement,'' Hans Blix, a former IAEA director and chief UN weapons inspector, told Reuters at the Vienna meeting.

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