Spain is imposing border controls on all travel from Italy following its threat to retaliate after Rome introduced similar measures.
The Spanish government said it would conduct passport, nationality and visa checks for Italian passengers and visitors arriving from Italy over the next month amid the country’s “persistent irregular migratory pressure”.
Italy declared earlier that it would not bow to “ultimatums or impositions” from Spain, confirming its intention to maintain border controls on arrivals from the country until at least 15 August.
It came after Madrid demanded Rome lift its border checks, which were imposed last week following a significant influx of migrants from Morocco into the Spanish enclave of Ceuta, by Sunday.
In a statement, the Italian government clarified that it would only reconsider its decision once it was assured there were no security or terrorism risks, no new migration wave, and no irregular migrants making their way towards European territory.
The Spanish government, for its part, condemned Italy's move to reintroduce checks on arrivals from Spain as "unjustified, contrary to the interests of the European Union and discriminatory against the Spanish population".
"If it fails to (remove the controls) before Sunday, August 9, Spain will be forced to adopt proportionate measures to protect the interests and dignity of its citizens," it said.
About 80 migrants died as 72,000 people rushed to cross the border. Italy, which does not share a land border with Spain, justified its decision to partially suspend the EU's border-free Schengen arrangements with Spain to prevent any of the migrants who entered Ceuta from travelling on to Italy.
Madrid said the Italian move was based on "spurious arguments" that lacked any factual basis because the migrants who entered Ceuta irregularly could not gain access to the Schengen area. It added that most of them have already left the North African enclave and returned to Morocco. Italy did not immediately comment on the latest Spanish statement.
Italy and Spain split on migration policy
The dispute between the two EU allies marks a new low in relations between Italy's conservative prime minister, Giorgia Meloni, and Spain's Socialist leader, Pedro Sanchez.
Meloni has positioned herself as one of Europe's leading advocates of tighter immigration controls, while Sanchez has generally defended a more liberal approach and recently backed a large-scale regularisation programme for undocumented migrants.
In Friday's statement, the Spanish government said Italy had registered the highest number of "irregular crossings in recent years", with figures that have been double those of Spain.
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