North Korea, Egypt, Israel, Lebanon and Syria are "unfairly" refusing to join the convention banning chemical weapons which has been signed by 180 countries, the head of the body monitoring the treaty said at the UN on Friday.
"It is very unfair to other countries if a few countries retain for themselves the privilege of producing chemical weapons when all the others are transparent in this field," said Rogelio Pfirter of Argentina, director general of the Organization for the Prohibition of Chemical Weapons (OPCW).
The convention, signed in 1993, entered into force in 1997 and mandated the OPCW to eliminate chemical weapons -- including deadly nerve gases -- forever.
Its mission also included the verification of the destruction of the declared chemical weapon stockpiles within the stipulated deadlines.
Pfirter, who briefed the General Assembly, bemoaned the fact that North Korea has spurned calls to join the treaty despite "allegations of the potential existence of stockpiles."
Last week, the UN Security Council unanimously agreed to slap sanctions on North Korea over its first-ever atom-bomb test and demanded that Pyongyang rid itself of all its weapons of mass destruction.
Pfirter also took Israel, Egypt, Lebanon and Syria to task for refusing to join the chemical weapons ban treaty.
He said "there could be no moral, strategic or legal excuse to remain outside" the convention, which given the number of signatories, is considered customary international law.
"Having even a single state outside the convention provided a major loophole that allowed the manufacture of very deadly weapons at the expense of humanity," he noted.
Each OPCW member state is mandated to declare if it is in possession of chemical weapons. States possessing chemical weapons must undertake a commitment to destroy all stockpiles by a particular deadline, initially next year, with an ultimate deadline of 2012.
Pfirter told during a press conference that while his organization, based in The Hague, was totally independent and technically not a part of the UN, it was guided by the same aspirations for peace and international security.