Austrian authorities have stated that troops may go to the Brenner Pass, unless the flow of migrants from Italy decreases.
"I think that border controls will be activated very soon and an army deployment will be necessary," Austrian Defence Minister Hans Peter Doskozil told the Kronen Zeitung daily on Tuesday.
Austrian Foreign Minister Sebastian Kurz has since defended the plan.
"Our preparations for controls at the border with Italy are not only just, but also necessary," Kurz said.
"We are preparing to defend our border at the Brenner if that is necessary."
Four Pandur armoured personnel carriers have reportedly been taken to the Brenner Pass and the deployment of the 750 troops could be activated within three days.
The Italian foreign ministry in Rome said in a statement that the Austrian Ambassador to Rome, René Pollitzer, had been summoned on Tuesday morning by the ministry's Secretary General, Ambassador Elisabetta Belloni, following the declaration.
Both Foreign Minister Angelino Alfano and Interior Minister Marco Minniti said the Austrian initiative was completely unjustified.
“There is no justification for this attitude; no one passes through the Brenner," Alfano said.
"I am frankly surprised by the statements of Doskozil, as it is clear there is no emergency at the Brenner Pass and cooperation with the Austrian police works perfectly," Minniti added.
With ANSA
