UNITED NATIONS — Iran is accusing the US Navy of carrying out “illegal and provocative acts” in the Persian Gulf and Sea of Oman.

In identical letters to UN Secretary-General Ban Ki-moon and the Security Council, Iran’s UN Ambassador Mohammad Khazaee said the Navy repeatedly violated the country’s airspace.

He cited flights over the coastal areas of Bushehr on seven occasions in October and most recently a US drone flight on Nov. 1 which disregarded all radio warnings and penetrated Iranian airspace.

The letters, circulated Friday, urged Ban to warn the US “against the continuation of acts in violation of international law and of the adverse consequences of any provocative and dangerous acts for which the United States government would be held responsible.”

The White House had no comment Friday night.

In related news, the US says a proposed conference on banning nuclear weapons in the Middle East cannot be convened at this point because of current conditions in the region.

State Department spokeswoman Victoria Nuland said in a statement released Friday that the US will continue to work to create conditions that could result in a successful conference. But she cited political turmoil in the region and Iran’s defiant stance on nonproliferation.

Nuland says the US supports the goal of a Middle East free of weapons of mass destruction. But she said such a conference should discuss a broad agenda of regional security.

“We would not support a conference in which any regional state would be subject to pressure or isolation,” Nuland added, alluding to Israel.

Iran and Arab nations have long criticized the West for supporting Israel and its widely suspected nuclear weapons program. Washington and its allies say Iran, North Korea and Syria are the greatest proliferation threats, even though Tehran and Damascus deny allegations of secret nuclear activities linked to weapons.