Senator Patrick Leahy is in Ireland joining an international appeal to ban cluster munitions because they kill and main too many civilians.
Negotiators from 110 governments are expected to unveil a treaty later this week restricting the development, sale and use of cluster munitions. The treaty would be signed in December in Norway.
Each cluster bomb drops dozens to hundreds of separate "bomblets.” Some explode days or even years later.
Leahy says indiscriminate weapons have no place in the 21st century. He has led American efforts to outlaw cluster munitions and provide support to their civilian victims.
The treaty talks does not involve the United States, Russia, China, Israel, India and Pakistan.