* France blocks trains carrying African migrants at frontier
* Italy Foreign Ministry makes formal embassy protest
* Interior minister says French stance “incomprehensible”
(Updates with train traffic resuming, French comment)
ROME, April 17 (Reuters) - France temporarily shut its border to trains from Italy carrying African migrants and protesters on Sunday, a move Rome formally protested, accusing Paris of violating European principles.
Italian railway and border police said France was preventing all trains passing the Ventimiglia-Menton border.
Italian Foreign Minister Franco Frattini instructed Italy’s ambassador in Paris to express “the firm protest of the Italian government to the French authorities”, a Foreign Ministry statement said.
France’s actions appear to be “illegitimate and in clear violation of general European principles”, it said.
Italy has complained about being “left alone” by European Union partners to deal with thousands of mainly Tunisian migrants who have arrived on its southern island of Lampedusa in recent weeks, fleeing political turmoil in North Africa.
It has began issuing migrants with temporary permits allowing them to leave Italy to travel to other destinations in Europe, a policy which has been criticised by several of its partners, including France and Germany.
Some of the countries in the 27-nation EU are worried that offering shelter to too many migrants will encourage more to attempt illegal entry to Europe.
Rail traffic across the border resumed early in the evening, the French Interior Ministry said. A ministry spokesman called the halt a temporary measure that he attributed to a demonstration “that hadn’t been authorised”.
Hundreds of Italian demonstrators gathered at the station at Ventimiglia to protest against France’s actions, chanting anti-French slogans and trying to persuade police to allow them to demonstrate outside the French consulate at Menton.
Interior Minister Roberto Maroni said in a television interview on Sunday that France’s stance was “incomprehensible” and “tough and unjustified towards Italy”.
He said he hoped “friendly relations” could be re-established with France at a summit meeting on April 26, where immigration will be near the top of the agenda.
This month, the interior ministers of France and Germany agreed to set up joint patrols off the Tunisian coast to deter would-be migrants and Rome has also pledged assistance to Tunisia to try to halt the flow. (Additional reporting by Gerard Bon in Paris; Writing by Gavin Jones; Editing by Jeffrey Heller)