The United Nations flag flies outside the U.N. Headquarters in New York

By Maria Kiselyova and Anastasia Teterevleva

MOSCOW (Reuters) - Russia on Tuesday summoned a senior U.S. diplomat in Moscow to protest over what it said was Washington's unacceptable refusal to issue visas to members of a Russian delegation traveling to the United Nations General Assembly.

The Kremlin promised a tough response and said Jon Huntsman, the U.S. ambassador in Moscow, had been summoned to the foreign ministry, but Russian news agencies said that Huntsman's deputy had gone instead.

Moscow said 10 members of a Russian delegation traveling to attend the United Nations General Assembly in New York had not been issued visas by U.S. authorities.

Maria Zakharova, a spokeswoman for Russia's Ministry of Foreign Affairs, said U.S. officials had returned the relevant visa application documents saying they had been submitted too early.

There was no immediate comment from the U.S. Embassy.

Zakharova said Russian Foreign Minister Sergei Lavrov would raise the issue with U.S. Secretary of State Mike Pompeo in New York.

She described the U.S. move as a violation of Washington's international commitments.

"This is an outrageous example of disrespect by the United States of America for members of the United Nations, as well as a failure to fulfill its obligations as host country to the world organization," Zakharova said on Facebook.

"Another act of disregard for the rights of sovereign states and international organizations and the inability to somehow comply with their own international legal obligations will be the central theme of the conversation between Lavrov and Pompeo in New York."

U.S.-Russia ties remain strained by everything from Syria to Ukraine as well as allegations of Russian interference in U.S. politics, which Moscow denies.





(Editing by Andrew Osborn)