Kosovo and Serbia have been told to put their differences aside so that both countries can resume membership talks with the EU.
Talks between the two countries broke down in November when Kosovo slapped a 100% tax on Serbian and Bosnian goods to retaliate against them not recognising the land-locked territory as a country.
Britain, France, Germany, Italy and the US said in a joint statement on Tuesday that "the status quo" preventing Serbia and Kosovo from continuing on the path towards EU membership "is simply not sustainable".
"Therefore, we call on Kosovo and Serbia to restart the EU-led dialogue with urgency and ask that both parties avoid actions that will hinder a final agreement," the allies said.
They added that compromises will need to be made.
"For Kosovo, that means suspending the tariffs imposed on Serbia. For Serbia, that means suspending the de-recognition campaign against Kosovo," they said.
Kosovo declared independence from Serbia in 2008 following a decade of deadly ethnic and religious conflict between the two entities and after Finnish-led negotiations yielded little.
The EU brought the two parties back to the negotiating table in 2011 resulting, two years later, in the signing of the Brussels Agreement which normalised relations between them.
The director of the Serbian Office for Kosovo, Marko Djuric, told reporters on Tuesday that the country would resume talks with Kosovo "once tariffs are abolished".
He added that "by no means does Pristina have the right to seek membership in international organisations" and that Belgrade's "policy toward Kosovo will be guided by interests."
Euronews contacted the Kosovan government for comment.