Belgrade has expelled the Montenegrin and Macedonian ambassadors in reaction to the two countries' recognition of Kosovo, reports said Friday.
Podgorica and Skopje recognized Kosovo, a territory Serbia still claims as its province, Thursday night, some eight months after it unilaterally declared independence.
Though it was certain to strain ties with Serbia, a major trade and economic partner, Montenegro and Macedonia jointly said they "remain committed to further promotion of ... relations with Serbia."
Montenegrin ambassador, Anka Vojvodic, was immediately told she had 48 hours to leave Serbia. "It is not a clever and political move," Vojvodic was quoted as saying.
Montenegro and Macedonia brought the tally of countries that now recognize Kosovo to 50.
"The reason why we opted for this sharp measure ... is because the decision in Podgorica came a day after the vote in the UN," Serbian Foreign Minister Vuk Jeremic told radio B92, referring to a decision Wednesday by the UN General Assembly to give the green light to a Serbian resolution calling on the International Court of Justice to rule if Kosovo's independence was in accordance with the international law.
Kosovo welcomes recognition
Kosova's President Fatmir Sejdiu, center, and Prime Minister Hashim Thaci, left, have enjoyed strong support from the West
Kosovar Prime Minister Hashim Thaci greeted the joint decision to recognize Kosovo as independent, saying the decision would strengthen peace in the region.
"On behalf of the institutions of the Republic of Kosovo, I would like to thank and welcome the governments of two neighbouring countries Montenegro and Macedonia for the recognition of Kosovo," he told reporters.
"The decision... (will) strengthen even more peace, stability and regional cooperation.”
But the Serbian president, Boris Tadic, labelled the moves by Macedonia and Montenegro irrational and counterproductive.
Serb President Boris Tadic says recognition of Kosovo as independent threatens stability
"The decisions of the governments of Montenegro and Macedonia to recognise the illegally proclaimed independence of Kosovo are very wrong, opposite to international law and do not contribute to regional stability and good neighbourly relations," Tadic said in a statement.
"By such a move the government of Montenegro... has jeopardised sovereignty and territorial integrity of Serbia. By doing so, a serious harm was done to citizens of both Serbia and Montenegro who have so much in common.”
Belgrade had previously withdrawn for consultations its own ambassadors from countries that recognized Kosovo since it broke away from Serbia in February.
Hours before Montenegro and Macedonia recognized Kosovo, Serbian ambassadors who had previously been withdrawn from abroad were told to return to their posts "to continue the diplomatic effort to keep Kosovo Serbian.”
Despite support from the world's richest countries, such as the United States, the majority of European Union nations and Japan, Kosovo's full-fledged promotion to nation status was blocked in the UN by Serbia's ally Russia.