* Italy migrant arrivals, deaths down a quarter this year
* Italy seeking to block migrants in Libya
* U.N. agencies say migrants trapped in shocking conditions
By Steve Scherer
ROME, Oct 18 (Reuters) - Prime Minister Paolo Gentiloni said on Wednesday that Italy was a model for Europe on how to reduce migrant arrivals, a day after U.N. agencies said its policies had trapped tens of thousands of people in dire conditions in Libya.
"Italy is proud to be a good example on the issue of migrants," Gentiloni told parliament before attending a meeting of European Union leaders where immigration policy will be discussed in Brussels on Thursday and Friday.
"We have reduced the number of people dying at sea and the number of irregular-migrant arrivals," he said.
Sea arrivals to Italy and deaths recorded in the Central Mediterranean are down by a quarter so far this year. On Wednesday, EU border agency Frontex said September arrivals dropped by two thirds versus a year earlier.
After more than 600,000 arrivals from North Africa -- mostly Libya -- in less than four years, Italy trained and equipped the Libyan coast guard, and an Italian navy ship is in Tripoli's port to repair vessels used to turn back migrant boats.
With a national election due in the spring, Rome has promised tens of millions of euros to Tripoli and to local authorities to help them shut down people smuggling.
The European Union has left Italy largely on its own to deal with Libya, where there are hundreds of armed militias and two rival governments vying for power six years after the ouster of Muammar Gaddafi.
More than 20,000 migrants have been trapped in farms, houses and warehouses around Sabratha, the U.N. refugee agency (UNHCR) estimates, in a situation of "human suffering and abuse on a shocking scale," spokesman Andrej Mahecic said on Tuesday.
"Amongst the refugees and migrants who suffered abuse at the hands of smugglers, there are pregnant women and new born babies," Mahecic said.
While Gentiloni said there must be an increase in resources for the migrants in Libyan camps, he added that Italy's success in reducing migrant arrivals was "very positive".
The United Nations, on the other hand, is calling for Europe to create safe and legal pathways to Europe for refugees and migrants so that they will not try to reach Europe by making the dangerous journey through Libya.
(Additional reporting by Stephanie Nebehay in Geneva)
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