BELGRADE, Serbia (AP) — Four Balkan countries on Monday threatened to retaliate if Croatia does not revoke its decision to raise taxes for fruit and vegetable imports.

Serbia, Bosnia, Macedonia and Montenegro issued an ultimatum to Croatia after a meeting of government officials in the Bosnian capital of Sarajevo.

Croatian officials said the measure was imposed on 168 non-EU countries to improve the quality of the imports, and was not meant to hurt the regional neighbors' economies — although the four are the main exporters of fruit and vegetables to Croatia.

The four countries demanded that Croatia revoke its decision to drastically raise the import fees. According to the new rates imposed by Croatia last week, a border sanitary inspection certificate for fruit and vegetables now costs 270 euros per truck, from 12 euros previously.

Serbian Trade Minister Rasim Ljajic said Croatia's neighbors don't want a trade war, but warned of retaliatory measures if Croatia doesn't return to the previous tax rates by the end of this week.

Croatian Agriculture Minister Tomislav Tolusic said that he expects to resolve the issue "in a week or two after we see what the problem is."

He called the four countries' officials to meet in Zagreb, the Croatian capital, next week to discuss the issue. He suggested Monday.

Economists say Croatia's measure is intended to protect its agriculture producers from cheaper imports. But, they say, the measure could backfire if there is a blockade of Croatian exports to the four countries.

The region was at war in the 1990s during the bloody breakup of the former Yugoslav federation.