Pakistan minister of State for Environment Maj Tahir Iqbal (retired) has called upon the developed nations to share their experiences with developing countries and help them initiate effective measures for checking Ozone-layer depletion. He was speaking at the open ceremony of the three-day Regional Meeting of South Asia Network Countries on 'Effective Policy Setting and Enforcement', here on Monday. The meeting has been jointly organized by the Ministry of Environment and United Nations Environment Programme (UNEP).