Iran's United Nations (U.N.) Ambassador Gholamali Khoshroo speaks at a United Nations Security Council meeting at the U.N. headquarters in New York, July 20, 2015. REUTERS/Mike Segar

UNITED NATIONS (Reuters) - The United Nations should hold the United States accountable for re-imposing sanctions on Monday to choke off Iran’s oil and shipping industry, measures that defy a U.N. Security Council resolution, Iran’s U.N. ambassador wrote in a letter to Secretary-General Antonio Guterres.

“The irresponsible conduct of the United States necessitates a collective response by the international community in order to uphold the rule of law, to prevent undermining diplomacy and to protect multilateralism,” Iranian U.N. Ambassador Gholamali Khoshroo wrote, calling for the United States to be held responsible.