The appointments have heightened tensions with the country's Serb minority and led to the wounding of 30 soldiers from the NATO-led international peacekeeping force KFOR in clashes with ethnic Serbs in the city of Zvecan.
Excluded from military exercise
The US ambassador in Pristina, Jeffrey Hovenier, says Kosovo is excluded from the Defender 23 exercise in which some 20 countries are participating, which will continue until June.
The exercise is over for Kosovo," Hovenier told local media.
Ambassador Hovenier also threatened to withdraw U.S. diplomatic support and to stop advocating international recognition of Kosovo.
The United States led the NATO operation that forced Serbian forces out of Kosovo in 1999 and has since supported the territory with an Albanian-majority and Albania's 2008 declaration of independence, which Serbia firmly rejects.
US Secretary of State Antony Blinken is also now criticizing Kosovo's Prime Minister Albin Kurti for his decision to appoint the ethnic Albanian mayors because it "forcefully and unnecessarily increased tensions".
Blinken called on all parties involved to take immediate action to reduce tensions while condemning the violence against the peacekeeping force.
See in the clip the violent clashes between security forces and Serbian protesters on Monday, which increased political unrest in the country.
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Serbian protesters clash with NATO soldiers in Kosovo. Photo: Social Newswire