Washington, May 04, 2019, SPA -- The United States has tightened sanctions on Iran by increasing restrictions on Iran's nuclear program. The US State Department said in a statement today that any assistance to expand Iran's Bushehr nuclear power plant could be subject to sanctions as well as to any activities involving the transfer of enriched uranium outside Iran to replace it with natural uranium. State Department spokesperson Morgan Ortagus said that Iran must stop all proliferation sensitive activities, including uranium enrichment, adding that the United States would not accept the actions that support the continuation of such enrichment, and will no longer accept to allow Iran to store the heavy water produced by it. --SPA 13:52 LOCAL TIME 10:52 GMT 0002 www.spa.gov.sa/w1096389