Speaking to the press after meeting parliamentary party heads to discuss Sunday's EU mini summit on migrations, Cerar said Slovenia protected the outer Schengen border suitably.
The Austrian exercise was thus not needed. "I even see it as somewhat provocative," Cerar said.
Austria carried out a major exercise encompassing around 500 police officers and 220 soldiers near the Spielfeld border crossing with Slovenia.
According to Austrian Interior Minister Herbert Kickl, the exercise was in no way a show of potential mistrust in Slovenia.
"Of course we trust the Slovenian police," he added, noting that the exercise could have been carried out at any border crossing.
The exercise had been initially scheduled for Monday, Slovenia's Statehood Day, but was postponed after protests from Slovenia.
"This was no problem for us. It was important for Slovenians and because of good neighbourly relations it was understandable that we decided to postpone the exercise," Kick told the press at Spielfeld today.
He added that Austria cooperated "very well with all neighbouring countries, including Slovenia" and worked closely with partners in the Western Balkans.
On the other hand, Cerar said that the exercise would have been justifiable if an increase in migrations had been recorded. "But no influx of illegal migrants from Slovenia to Austria has been recorded," Cerar stressed.
He added that Slovenia advocated strengthening controls at the outer EU borders, while the country itself was "an exemplary protector of the Schengen border" which was why Austria's control of the border was not justified.