North Korea is helping Iran to prepare an underground nuclear test similar to the one Pyongyang carried out last year, a media report said on Wednesday.
Under the terms of a new understanding between the two countries, the North Koreans have agreed to share all the data and information they received from their successful test last October with Tehran's nuclear scientists.
North Korea had invited a team of Iranian nuclear scientists to study the results of last October's underground test to assist Tehran's preparations to conduct its own test -- possibly by the end of this year, The Daily Telegraph quoted a senior European defence official as saying.
"The Iranians are working closely with the North Koreans to study the results of last year's North Korean nuclear bomb test," said the European defence official.
North Korea provoked an international outcry when it fired a bomb at a secret underground location and Western intelligence officials are convinced that Iran is also working on a weapons programme.
There were unconfirmed reports at the time of the Korean firing that an Iranian team was present.
Iranian advisers regularly visit North Korea to participate in missile tests.
Now the long-standing cooperation has been extended to the nuclear issue, the report said.
Senior western military officials are deeply concerned that the North Koreans' technical superiority will allow the Iranians to accelerate development of their own nuclear weapon.
"We have identified increased activity at all of Iran's nuclear facilities since the turn of the year," he said. "All the indications are that the Iranians are working hard to prepare for their own underground nuclear test."
The disclosure comes as Tehran seems set on a collision course with the West over its nuclear programme, although it insists it is entirely peaceful.
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