Italy has summoned Austria's ambassador after the government in Vienna announced it was ready to deploy border troops to block any migrant influx.
Austrian Defence Minister Hans Peter Doskozil told Kronen Zeitung daily that troops could go to the Brenner Pass.
He said four Pandur armoured personnel carriers had been sent to the Tyrol region and 750 troops were on standby.
Austria has border checks with Hungary and Slovenia. But elsewhere it adheres to the EU open borders system.
Mr Doskozil said a military deployment at the busy Alpine pass, on the Italian border, would be "indispensable if the influx into Italy [across the Mediterranean] does not diminish".
Later Italy's foreign ministry said it had summoned Austrian Ambassador Rene Pollitzer "following the Austrian government's statement about deploying troops to the Brenner (pass)".
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http://www.bbc.co.uk/news/world-europe-40491497