NATO forces have occupied a border crossing with Serbia in Northern Kosovo after it was fire bombed and bulldozed by ethnic Serbs.
The Kosovo government in Pristina previously sent police officers to take control of two crossing points and enforce a new ban on imports from Serbia.
The dispute is over customs regulations.
Prime Minister Hashim Thaci said he would not negotiate with Belgrade over the border issue as it was an internal matter.
Kosovo declared independence in 2008, but Serbs who live in northern Kosovo still consider Belgrade their capital.