NATO secretary general Lord Robertson and EU foreign policy chief Javier Solano have cancelled a trip to Macedonia amid fears that peace talks aimed at preventing a civil war could collapse.
The pair cancelled their flight to Skopje after Macedonia's ruling party bluntly rejected a peace proposal brokered by the US and the EU.
Prime Minister Ljubco Georgievski slammed the Western peace plan, saying it is tailored to break up Macedonia.
One of the main objections to the plan is a demand from the ethnic Albanian minority that Albanian be recognised as an official language alongside Macedonian.
The draft peace plan retains Macedonian as the primary language and maintains central state control of the police, but it proposes that Albanian be declared the main language in some regions.
The peace talks are currently in their 12th day, but this latest development could cause the negotiations to break up, leading to the end of a two-week ceasefire and the resumption of the ethnic Albanian insurgency, which began in the north of the country last February.