Resolution 635 (1989) of 14 June 1989
The Security Council,
Conscious of the implications of acts of terrorism for international security,
Deeply concerned by all acts of unlawful interference against international civil aviation,
Mindful of the important role of the United Nations in supporting and encouraging efforts by all States and
intergovernmental organizations in preventing and eliminating all acts of terrorism, including those invoking
the use of explosives,
Determined to encourage the promotion of effective measures to prevent acts of terrorism,
Concerned about the case with which plastic or sheet explosives can be used in acts of terrorism with little
risk of detection,
Taking note of the International Civil Aviation Organization Council resolution of 16 February 1989, in which
it urged its member States to expedite current research and development on detection of explosives and on
security equipment,
1. Condemns all acts of unlawful interference against the security of civil aviation;
2. Calls upon all States to co-operate in devising and implementing measures to prevent all acts of terrorism,
including those involving explosives;
3. Welcomes the work already undertaken by the International Civil Aviation Organization, and by other
international organizations, aimed at preventing and eliminating all acts of terrorism, in particular in the
field of aviation security;
4. Urges the International Civil Aviation Organization to intensify its work aimed at preventing all acts of
terrorism against international civil aviation, and in particular its work on devising an international regime
tor the marking of plastic or sheet explosives for the purpose of detection;
5. Urges all States, and in particular the producers of plastic or sheet explosives, to intensify research into
means of making such explosives more easily detectable, and to co-operate in this endeavour;
6. Calls upon all States to share the results of such research and co-operation with a view to devising, in the
International Civil Aviation Organization and other competent international organizations, an international regime
for the marking of plastic or sheet explosives for the purpose of detection.
Adopted unanimously at the 2869th meeting.