Even as Pakistan continues to urge the international community to accept its membership to the Nuclear Suppliers Group, highly placed sources in the United States who are involved with the tracking of nuclear commerce have claimed that Islamabad is still selling nuclear materials to North Korea.
In making this dramatic revelation, the sources said that entities of the Pakistan Energy Commission have been continuing to supply restricted items such as Monel (a nickel-copper alloy with high tensile strength and resistance to corrosion) and ' Inconel (an alloy of nickel containing chromium and iron, resistant to corrosion at high temperatures) material to North Korea in violation of UN sanctions.
The sources said that nuclear materials supplied to the PAEC by Chinese entities have also found their way to North Korea, with the China Atomic Energy Authority recently receiving a written complaint that supplies of a Chinese company, Beijing Suntech Technology Company Limited, to Pakistan were being diverted to North Korea by the Pakistani authorities.
The Chinese government hushed up the matter, as it could have consequences for Beijing's bid to support Pakistan at the NSG.
But this information leaked out of North Korea and came to the knowledge Of Western governments who are members of the NSG.
In another alarming revelation, informed sources said Pakistan has been giving North Korea equipment which has a direct bearing On producing nuclear weapons.
Sources said the Beijing Suntech Technology Company Limited manufactures Vacuum Induction Melting furnaces, which find application in refining hard metals such as uranium and plutonium, which are used in making nuclear warhead cores.
Pakistan is known to have procured these items from China and has passed them along to North Korea.
When asked if this evidence of Pakistan's illicit nuclear trade with North Korea has been brought to the notice of NSG nations, US sources said all evidences which confirm the violation of sanctions against North Korea and more so the ongoing dangerous nuclear trade has been brought to the notice of "those who need to be informed at the NSG level."
Behind the scenes, Pakistan is aware that its nuclear trade with North Korea has been uncovered, but is counting on China to keep the global pressure at bay, said sources.
Giving details of North Korea's nuclear commerce links with Pakistan, informed sources mentioned that two North Korean diplomats -- Kim Yong Choi and Jang Yong Son -- posted in the North Korean Embassy in Tehran visited Pakistan eight times between 2012 and 2015.
They were associated With the Korea Mining Development Trading Corporation -- an entity sanctioned several times by the United Nations Security Council since 2005 for its involvement in North Korea's Weapons of Mass Destruction programme.
These diplomats met Pakistani officers involved in the nuclear programme. They were tracked and investigated by the Western authorities as yet another proof of Pakistan's continuing nuclear links with North Korea.
Based on Western inputs on these links, the United Nations Security Council 1718 Committee, which is monitoring the implementation of sanctions against North Korea, sought information from Pakistan in November 2015 regarding the frequent visits of the two North Korean diplomats from Tehran to Islamabad and Karachi.
At first, say informed sources, Pakistan denied it, but when confronted with photographs and other recorded evidence, Pakistan acknowledged that the two North Korean officials under investigation had indeed visited Islamabad and Karachi.
Highly-placed sources said that the West has so far kept this information under wraps in recognition of Pakistan's value in the war against terror.
But now, when Pakistan has gone into overdrive to upset the equilibrium of the NSG, Western nations of the grouping are saying that Islamabad needs to "look at itself in the mirror " and ask "how can it run with the hare and hunt with the foxes", meaning it can't claim to fulfill the NSG's requirements, and at the same time, sell nuclear weapons materials to North Korea.