UNITED NATIONS, April 6 (Xinhua) -- The United Nations is alarmed by the U.S. rhetoric that threatens attacks on Iran's power plants and bridges, a UN spokesperson said Monday.

"We were alarmed by the rhetoric seen in that social media post that threatened American attacks on power plants, bridges, and other infrastructure should Iran not agree to a deal," Stephane Dujarric, chief spokesman for UN Secretary-General Antonio Guterres, said at a daily briefing.

"The secretary-general has been very clear on issues regarding international law, and he urges yet again all parties to abide by their obligations regarding the conduct of these hostilities," he said.

Guterres recalls that civilian infrastructure, including energy infrastructure, may not be attacked, even if specific civilian infrastructure were to qualify as a military objective, the spokesperson added.

"Once again, the secretary-general reaffirms that it's high time for the parties to stop this conflict as there is no viable alternative to the peaceful settlement of international disputes," he said.

When asked if such attacks could constitute war crimes in the UN chief's view, Dujarric said that "they would constitute violations of international law" and that whether it is a crime or not "would have to be decided by a court."

"But any attack on civilian infrastructure is a violation of international law, and a very clear one," he said. ■