Officials in Dubrovnik, a tourist hotspot in southern Croatia known as the “Pearl of the Adriatic”, fear it could become part of a new route for thousands of migrants as they seek to avoid a security fence that is growing along Hungary’s borders.

Up to 10,000 migrants a day are now entering Croatia through its eastern border with Serbia, after Hungary sealed its own 175km-long frontier with Serbia by means of a controversial four-metre-high steel barrier topped with razor wire.

For almost a fortnight, Croatia has helped migrants get round the costly fence – much to the annoyance of the Budapest government – by bussing them to the Croatia-Hungary border, from where Hungary transports them to Austria.

Hungary’s prime minister, Viktor Orban, says an extension to the fence along his country’s border with Croatia is now almost complete, however, causing alarm in neighbouring states over which new path it will force migrants to take.

“I ask the government not to allow refugees to enter the Republic of Croatia on the territory of Dubrovnik-Neretva county,” the head of the region, Nikola Dobroslavic, wrote to the country’s prime minister, Zoran Milanovic.

In a letter widely quoted in Croatian media, Mr Dobroslavic urged Mr Milanovic to help “ensure the normal operation of the tourist season, which in our county is still in full swing, and prevent negative effects on tourism in Dubrovnik and the tourist destinations of the Dubrovnik coastline.”

More southerly route

“The southern route goes [from Greece or Macedonia] through Albania and Montenegro to Croatia, and they could cross the [Croatian] border at Konavle, or follow the Neretva river,” he told Croatian media.

Konavle is a Croatian region just south of Dubrovnik that borders Montenegro and Bosnia, while the Neretva river flows from Bosnia into the Adriatic Sea about 100km north of Dubrovnik.

Regional officials said contingency plans were being made to provide temporary accommodation for several thousand migrants, most of whom are from Syria, Iraq and Afghanistan, at a former Yugoslav military facility at Prevlaka, a peninsula 50km south of Dubrovnik, and at other locations in the area.

Speaking at the Opatovac transit camp in the Slavonia region of northeast Croatia, interior minister Ranko Ostojic said his country had “to be ready” for anything, as Europe faces its worst refugee crisis since the second World War.

“Whatever happens, we can’t allow ourselves to be unprepared. The things we’ve done here in Slavonia, we will do in southern Croatia if it comes to that. Preparation is all-important. I don’t want to spread panic, but everything is ready.”

Montenegro’s government also said it was preparing for migrants to arrive in the country, which has borders with Albania to the south, Kosovo and Serbia to the east and Croatia to the north. “With the latest developments at Hungary’s border [with Croatia] and the pressure on Macedonia and Serbia, it is possible that many refugees will choose to go through . . . Montenegro,” the AFP news agency quoted the government as saying.

Montenegro

Such a route towards Austria and Germany would be longer, harder and involve crossing more frontiers than the migrants’ current northerly path, but developments in the crisis have proved hard to predict, with some states changing border policies and even temporarily banning vehicles from neighbouring countries.

Since Hungary sealed its border with Serbia a fortnight ago, triggering brief clashes between migrants and Hungarian riot police guarding the security fence, more than 65,000 asylum seekers have entered Croatia from Serbia.

If Hungary were to prevent them being transported further, through its territory to Austria, Croatia’s transit facilities could quickly be overwhelmed. Croatia could then seek to prevent migrants entering from Serbia, or it could direct them westwards towards Slovenia, a fellow EU member that borders Austria.

Mr Orban suggested during a visit to Austria last Friday that he would not seal Hungary’s fence with Croatia before consulting and seeking support for the move from neighbouring states and the United Nations.

In an easing of regional tensions since Friday, Croatia and Serbia lifted restrictions on each other’s vehicles entering their territory, and Hungary removed spools of razor wire from its border with Slovenia.

“The key is that everything goes smoothly on Hungary’s side. [Hungary] is still receiving and transporting” migrants to the Austrian border, Mr Ostojic said. “The situation is under control.”