PRISTINA, Kosovo (AP) — Kosovo's president has ordered four Serb-dominated communities to hold new municipal elections on May 19.

Hashim Thaci said Monday the decision was taken "following consultations with political parties," a move that may aggravate already tense ties between Kosovo and Serbia.

Four mayors from the Serb-dominated northern municipalities in Kosovo resigned in November to protest the Kosovo government's 100% tariff on goods imported from Serbia.

Prime Minister Ramush Haradinaj has resisted international calls, saying the tariff will only be lifted when Belgrade recognizes Kosovo's sovereignty and stops preventing it from joining international organizations.

Serbia says it won't take part in European Union-mediated talks on normalizing ties with Pristina until Kosovo lifts the tax. Serbia doesn't recognize Kosovo's 2008 declaration of independence.