TEHRAN, Jan. 4 (Xinhua) -- Iran's ambassador to the United Nations Gholamali Khoshroo slammed the U.S. government's recent attempts to intervene in the domestic affairs of the Islamic Republic, Tasnim news agency reported on Thursday.

"In the past several days, the U.S. administration, led by the U.S. president, has stepped up its acts of intervention in a grotesque way in Iran's internal affairs under the pretext of providing support for sporadic protests" in the country, Khoshroo said in a Wednesday letter to the UN Security Council and to UN Secretary General Antonio Guterres.

"The current U.S. administration has crossed every limit in flouting rules and principles of international law governing the civilized conduct of international relations," the letter was cited as reading.

Khoshroo added that Iran expects all states condemn such dangerous statements and policies and urge the U.S. government to act responsibly and adhere to principles of the UN Charter and international law.

Over the past week, riots broke out in some Iranian cities in protest against price hikes and economic woes.

U.S. President Donald Trump and a number of other U.S. officials, including Vice President Mike Pence, have sided with the protesters.