BELGRADE – Serbia plans to seize a slice of northern Kosovo just as Russia annexed Ukraine’s Crimea region in 2014, Kosovo’s president Hashim Thaci told Reuters on Monday.

Kosovo special police units on Saturday prevented a train painted in Serbia’s national colors and bearing the words “Kosovo is Serbia” from crossing the border.

Serbia does not recognize the independence of Kosovo, and did not seek Pristina’s permission for the passage of the train, which it paid for and organized. On Sunday Serbia’s president, Tomislav Nikolic, said Kosovo’s action had shown it wanted war with Belgrade.

Thaci said the train was aimed at “provoking” Kosovars in order to create a pretext for Serbia to intervene militarily and annex northern areas of Kosovo, home to 50,000 ethnic Serbs who refuse to accept the province’s independence and want to be governed again by Belgrade.

“Serbia’s intention is to use this train, which was donated by Russia, first to help carve away the northern part of Kosovo and then … attach it to Serbia. It is the Crimea model,” Thaci said in an interview.

Serbia lost control of Kosovo when NATO air strikes forced Belgrade to withdraw its troops in 1999. NATO still has around 5,000 troops stationed in Kosovo to keep the fragile peace.

After talks with Serbia’s military top brass and state security chiefs in Belgrade on Sunday, Serbia’s President Tomislav Nikolic threatened to send troops back into Kosovo.

“If they are killing Serbs, we will send the army, all of us will go, I will go as well, it would not be my first time,” said Nikolic.

Responding to Nikolic’s remarks, Thaci said any attempt by Serbia to annex northern Kosovo would set off “a chain reaction across the whole Western Balkans”.