The United States is expected to ship 7 kg of HEU to Canada to support medical isotope production at the NRU reactor at Chalk River Laboratories. According to a report in Ottawa Citizen, NNSA requested a license for the shipment. According to the report, the United States has been supplying HEU for the NRU operations in 7 kg shipments that take place every 12 months. The most recent license, for shipment of 7.5 kg of HEU (No. XSNM3726), was issued by NRC in October 2012. The use of HEU at Chalk River is expected to stop by 31 October 2016, when the current NRU operating license expires.

While the NRU reactor is using LEU fuel, highly enriched uranium is used in targets to produce Mo-99. In 2010, the United States and Canada agreed to return irradiated HEU to the United States. The first shipment reportedly took place in 2010.

UPDATE 06/14/2013: In May 2013 NNSA applied for another license (XSNM3745) to export additional 7 kg of U-235 to Canada.