The head of the main opposition party in Serbia has resigned after senior colleagues refused to back the country’s efforts to join the EU.
Tomislav Nikolic had recently persuaded his Serbian Radical Party to approve the ratification of an important agreement with the European Union.
But there was a party revolt over the issue, with critics saying it meant abandoning Serbia’s claim to Kosovo.
Kosovo unilaterally declared itself independent from Serbia this year.
The BBC’s Nick Thorpe in Belgrade says Mr Nikolic had steered his party towards the centre of Serbian politics, focusing on social issues such as unemployment and poverty, rather than the militant nationalism of the past.
Mr Nikolic is officially the deputy president of the party as its leader, Vojislav Seselj is facing charges at the international war crimes tribunal in The Hague.
His endorsement of the Stability and Association Agreement, signed earlier this year but still awaiting ratification by the Serbian Parliament, was a bridge too far for many of his party colleagues, our correspondent says.
A meeting of the party leadership on Friday night reversed the decision to endorse the agreement with Brussels.
Mr Nikolic resigned in protest, both from his position as de facto leader of the party, and as the head of its group in parliament.
The parliamentary vote on the agreement with the European Union is expected next week.