The Tehran regime and the North Korean government have been engaged in extensive exchange of information and visits by experts on nuclear weapons and nuclear warhead design as recently as April 2015, reliable and detailed information obtained by network of the Iranian opposition movement, the Mujahedin-e Khalq (MEK) inside Iran say.

The MEK also provided a detailed account of a visit to North Korea in 2013 of Tehran’s top nuclear weapons experts headed by elusive Mohsen Fakhrizadeh, who was present during the last nuclear test conducted by North Korea.

Also a seven-member North Korean delegation, comprised of experts in nuclear warhead design and various parts of ballistic missiles including guidance systems, spent the last week of April in Iran. This was the third such nuclear and missile team to visit Iran in 2015. The next delegation is scheduled to secretly arrive in Iran in June and will be comprised of nine experts, according to the same MEK sources.

These experts have also provided assistance and consultation in the areas of aerodynamics, missile body design, and electronic components of warheads.

That Tehran continues to closely engage with North Korea, a country that cheated its way into making a nuclear weapon, all the while pledging that it would not do so, should be an additional cause for alarm and a red flag for the international community.

They stayed in the secret guesthouse, a cornered-off eight-story building, near a Hemmat Industrial Group site in the Khojir area, northeast of Tehran. Named “Imam Khomeini Complex,” and also known as 2000 units, the site is controlled by the Ministry of Defense (MoD)

While Fakhrizadeh’s presence during the North Korean’s 2013 nuclear test was first reported by the Sunday Times of London at the time, after a two-year investigation, the Iranian opposition has been able to confirm that Fakhrizadeh had gone to North Korea for the nuclear test through China under the alias of Dr. Hassan Mohseni.

The head of the Organization of Defensive Innovation and Research (SPND) and the key figure in activities concerning the military dimensions of the regime's nuclear program, Fakhrizadeh is a Brigadier General of the IRGC, with whom the IAEA has requested interviews.

The MEK first exposed the formation of SPND in July 2011 and the State Department placed SPND on its sanctions list in August 2014 as an “entity that is primarily responsible for research in the field of nuclear weapons development.”

According to the Iranian opposition reports, during the North Korea visit, Fakhrizadeh, accompanied by two other SPND nuclear experts, stayed in Hotel Koryo in Pyongyang. . To keep his visit secret, Mansour Chavoshi, Tehran’s Ambassador to Pyongyang, personally welcomed Fakhrizadeh and facilitated his communications and exchanges with North Korean officials. Fakhrizadeh spent only two hours in the Iranian regime’s embassy in Pyongyang and made no other visits to the embassy during this trip.

The new information is further indication that the drive to acquire nuclear weapons remains at the core of the Iranian regime’s program as the nuclear negotiations continue in Vienna and Geneva.

This conduct is in keeping with the positions of Supreme Leader Ali Khamenei and other senior officials, who reject IAEA inspections of military sites and interviews with nuclear scientists. Tehran’s objective is to continue its policy of concealment and duplicity in a bid to complete and advance its nuclear projects.

After three decades of concealment and deception, adding six or nine months to the breakout time will not lead to a solution.

That Tehran continues to closely engage with North Korea, a country that cheated its way into making a nuclear weapon, all the while pledging that it would not do so, should be an additional cause for alarm and a red flag for the international community about the ruling theocracy’s real intentions with its nuclear program.

Alireza Jafarzadeh, the deputy director of the Washington office of the National Council of Resistance of Iran, is credited with exposing Iranian nuclear sites in Natanz and Arak in 2002, triggering International Atomic Energy Agency inspections. He is the author of "The Iran Threat" (Palgrave MacMillan: 2008). His email is Jafarzadeh@ncrius.org.