An exterior view of the Italian embassy in Tripoli February 15, 2015. [Photo/Agencies]

ROME - Italy closed its embassy in Libya on Sunday and stepped up its call for a UN mission to calm the worsening conflict there as thousands of migrants approached Italy by boat from North Africa.

Libya is unravelling, with two rival governments operating their own armed forces under separate parliaments, nearly four years after the civil war that ousted leader Muammar Gaddafi.

"The deteriorating situation in Libya made it necessary to close (the embassy)," Foreign Minister Paolo Gentiloni said. Embassy staff have been sent back to Italy, the ministry said.

Violence appears to be intensifying in Libya, where Islamic State is also active.

The violence is particularly alarming to Italy because the two countries are separated only by a narrow stretch of the Mediterranean, across which migrants travel looking for a better life in Europe. Chaos in Libya has made it almost impossible to police traffickers who charge up to $2,000 for the passage.

Italy's coast guard, which was involved in a full-scale search and rescue mission until last year, has gone to rescue more than 2,000 people since Friday, days after more than 300 people died trying to make the crossing.