By Louis Charbonneau
UNTED NATIONS, March 11 (Reuters) - U.N. Assistant Secretary-General Ivan Simonovic, who is in Ukraine to assess the human rights situation, will not go to the pro-Russian Crimea region for the time being, the United Nations said on Tuesday.
"He plans to travel to Lviv tomorrow," U.N. spokesman Stephane Dujarric told reporters. "Regarding travel to Crimea, Mr. Simonovic has been informed that under the current circumstances, the security of his delegation cannot be guaranteed. As of now, he will not be travelling there."
The main airport in Ukraine's Crimea cancelled incoming flights from the capital, Kiev, but allowed several planes from Moscow to land on Tuesday, five days before a scheduled referendum on whether the autonomous Black Sea region should join the Russian Federation.
A Ukrainian airliner was turned back on its way from Kiev to Simferopol, Crimea's main city, and returned to the capital.
"With the situation changing very quickly, we're taking it day by day and looking at options," Dujarric said when asked if Simonovic considered travelling to Crimea from another country.
He said Simonovic was in eastern Ukraine's biggest city, Kharkiv.
"He met with local authorities there to discuss human rights-related measures that can help to de-escalate tensions, as well as allegations regarding human rights violations," he said. "He also met with a range of pro-Russian as well as pro-Ukrainian civil society representatives."
Last week another U.N. representative, Robert Serry, abandoned a mission to Crimea. He was stopped by armed men and besieged inside a cafe by a crowd shouting "Russia! Russia!"
A group of observers from the Organization for Security and Cooperation in Europe who traveled to Ukraine repeatedly was turned back from Crimea.
The east-west confrontation, sparked by last month's overthrow of President Viktor Yanukovich after violent protests in Kiev, escalated on Thursday when Crimea's parliament, dominated by ethnic Russians, voted to join Russia and called for a March 16 plebiscite on the issue.
Allegations of rights abuses in Ukraine have come from all sides in the crisis.
The new Kiev government said Yanukovich, a Russian ally, was guilty of rights abuses and murder for ordering a crackdown on protesters that left dozens dead.
Russia and pro-Russian Crimean authorities accused the opposition and new government of human rights abuses, including threats and harassment of ethnic Russians and Russian speakers in eastern Ukraine.
Western powers and Kiev said there was no evidence Russian speakers have been abused. (Additional reporting by Michelle Nichols; Editing by Amanda Kwan)