The US has said it is against the break-up of Bosnia, following a radical proposal widely attributed to incoming EU presidency Slovenia.
"The United States deeply values its longstanding partnership with Bosnia and Herzegovina. We support its sovereignty and territorial integrity, respect for which was enshrined in the Dayton Peace Accords," a state department spokesperson said on Thursday (15 April), referring to a 1995 peace deal which ended a bloody ethnic conflict.
The Croatian foreign minister, Grlić Radman, said the same one day earlier.
The comments arose after an informal policy paper, which came to light earlier this week, proposed an EU-led campaign to carve up the federation.
Its majority-ethnic Serb parts should join Serbia, its Croatian parts should join Croatia, and its rump would become an independent state for Bosniaks (Bosnian Muslims), the policy paper said.
Kosovo should also join with Albania to create another new country, the paper, which was sent to EU Council president Charles Michel in February, added.
There is little doubt in diplomatic circles that Slovenia's populist prime minister, Janez Janša, who takes over the symbolic EU presidency in July, was behind it.
This is what Bosnia believes, after it summoned Slovenia's ambassador to Sarajevo to complain earlier this week.
This is what US diplomats believe, speaking off the record.
And this is what EU diplomats told Slovenian daily
Necenzurirano.si, which published the informal paper in its entirety.
But for his part, the usually pugnacious Janša is keeping quiet - neither conforming nor denying the reports - amid the negative reactions.
In the past, he called two women journalists he did not like "worn-out prostitutes" in an infamous tweet.
In late March, he also called two MEPs he did not like "overpaid bureaucrats who were born into prosperity" and likened them to the late Serbian dictator Slobodan Milošević.
But when asked by EUobserver if he sent the paper to Brussels, his staff replied: "The office of the prime minister of the Republic of Slovenia does not further comment the topic on the so-called 'non-paper' document about the Western Balkans.
His EU embassy also declined to comment.
But with Brussels bracing itself for six months of potential controversy under Janša's presidency, a Slovenian spokesman tried to calm tension.
Redrawing borders on ethnic lines in the Western Balkans is widely seen as a recipe for renewed instability.
But the Slovenian spokesman said: "I can tell you that one of the main themes [of the presidency] will be a secure European Union, a good and reliable partner in the neighbourhood and in the world".
"The Slovenian presidency will dedicate particular attention to the Western Balkans and lead the Council of the EU in the direction of continuing the process of EU enlargement with the countries of the region," he added.
