NATO is ready to ramp up troops in Kosovo if tensions among minority Serbs flare again as a deadline in a spat with the government over car papers approaches, 1the deputy commander of the alliance's peacekeeping mission (KFOR) said on Tuesday.

"We are vigilant and ready to act...if we have an increase of tensions, but we can also draw on reserve forces...that we can call in at short notice," Brigadier General Luca Piperni told reporters at KFOR headquarters in the capital Pristina.

Unrest among Kosovo Serbs over a requirement for them to use state-issued car number plates has raised fears of conflict between Kosovo and Serbia, more than two decades after NATO bombed Serbia to end repression of Kosovo's Albanian majority.

Serbia does not recognise Kosovo's independence, won in 2008, and Serbs in northern Kosovo consider Belgrade, not Pristina, to be their capital. Around 3,700 NATO peacekeepers are still stationed in the former Serbian province to prevent violence between ethnic Albanians and Serbs.

Earlier attempts to introduce Kosovo licence plates in heavily Serb northern Kosovo led to clashes between police and local Serbs, who erected roadblocks. The barricades were only dismantled when NATO peacekeepers stepped in to oversee the process and Kosovo agreed to postpone the licensing rule.

Piperni said the situation was calm but fragile at the moment, and that NATO could not rule out fresh tensions or violence in the north as the Oct. 31 deadline approaches.

"If the situation deteriorates, we are ready to intervene, we are ready to be in the middle between the protesters and the security organisations," he stressed.

"We have sufficient forces to deal with the situation...With that amount of troops we can end any kind of increase of tensions," Piperni added, referring to troops outside Kosovo that NATO could draw as reinforcements.

Both Kosovo and Serbia aim to join the European Union and have agreed, as part of that membership process, to resolve their outstanding issues and build good neighbourly relations. (Reporting by Sabine Siebold Editing by Mark Heinrich)