The announcement comes after Hungary said it would seal off its border with Croatia at midnight, in a move that is expected to reroute the refugee flow further west to the Slovenian border.

Slovenian authorities have held a series of emergency meetings to get acquainted with the development and carry out the latest preparations for what is expected to be a much bigger wave of refugee arrivals than a month ago.

In addition to sending extra police to the border, Slovenia is currently in talks with Croatia on designated entry points for refugees, Györköš Žnidar said.

While the Croatian government said it would start implementing a "Plan C", which reportedly involves redirecting refugees to Slovenia, both Györköš Žnidar and Foreign Minister Karl Erjavec said they were not aware of such a plan.

Nor has the government been formally notified by Croatia that refugees will be sent to Slovenia, according to Györköš Žnidar.

During the first wave, refugee arrivals were concentrated on the south-eastern border, at the crossings of Obrežje and Rigonce. With Obrežje a key point of international goods flow, authorities will be keen to keep it clear this time around.

While Slovenia expects that the large majority of the refugees will want to move on to Austria and Germany, a subject of concern is whether these countries will continue to keep their borders open.

Erjavec said that his Austrian counterpart Sebastian Kurz had assured him that Austria would not be changing its policy as long as Germany continued to accept refugees.

Slovenian officials have in recent days indicated that Slovenia would be forced to seal off its border if Germany and Austria took such a step.

President Borut Pahor said in Milan today that Slovenia would have to close its border if that happened, an issue he recently discussed with his Austrian and German counterparts.

"They understand that Slovenia...would risk becoming a pocket for tens of thousands of refugees that we cannot provide for, even if we wanted to," he stressed. "We have to accept the refugees humanely, but at the same time make sure our measures protect law and order."

According to the latest police figures, Slovenia currently has capacity for accommodating around 7,500 refugees. This is a little more than the number of refugees who arrive in Croatia from Serbia on a daily basis.

Minister Györköš Žnidar would not speculate about how many refugees might start arriving, but she said the country was capable of handling more than are currently arriving.