The head of the European Union's executive branch has questioned whether Romania is ready for the political give-and-take of running the EU presidency, though he says the country is "technically well-prepared."

Romania takes over the rotating EU presidency for six months Jan. 1 amid deep political divisions at home and a contentious domestic judicial overhaul. The presidency will give it a role in setting the EU agenda and the task of serving as a diplomatic go-between among the 28 member countries.

European Commission President Jean-Claude Juncker was quoted Saturday as telling Germany's Welt am Sonntag newspaper that Romania is "technically well-prepared" in part thanks to the Commission's help.

"But I think the government in Bucharest hasn't yet fully understood what it means to take the chair over the EU countries," he added. "For judicious negotiations, you also need a readiness to listen to others and the firm will to put your own wishes aside. I have some doubts there."

Juncker also pointed to Romania's domestic divisions. There are long-running differences between President Klaus Iohannis and Liviu Dragnea, the chairman of the governing Social Democratic Party.

Iohannis last month said Romania wasn't up to the presidency. Dragnea then asked party colleagues to find a way to prosecute him for treason over those remarks. The president has since struck a more optimistic note.

Juncker was quoted as saying that Romania's domestic situation means it can't present itself as a "compact unit" in Europe.

"There needs to be a united front at home to foster unity in Europe as well during the presidency," he said.

Romania succeeds Austria in the EU presidency. Its six months at the helm will include Britain's planned exit from the bloc in March and elections to the European Parliament in May.

Maria Grapini, a European Parliament lawmaker with Romania's Social Democrats, said Juncker was being "duplicitous."

She told the private Mediafax news agency that, during a recent meeting with Romanian officials in Brussels, Juncker had said it was "clear ... that Romania was up to the presidency."

"You can't say it's black today and tomorrow it's white," she said.