* Leaders to discuss pact to end Kosovo partition

* Kosovo local election may be repeated in Serbian area

By Fatos Bytyci

PRISTINA, Nov 5 (Reuters) - Leaders of Serbia and Kosovo will meet in Brussels on Wednesday to discuss how to press ahead with a landmark accord to tackle Kosovo's de facto ethnic partition after violence marred local elections in the Balkan country.

A small Serb pocket of majority-Albanian Kosovo joined in Sunday's Kosovo-wide council and mayoral elections but voting had to be suspended after masked men attacked polling stations in the area, lobbing tear gas and smashing ballot boxes.

The violence underscored the challenge facing all sides in implementing the April pact, brokered by European Union foreign policy chief Catherine Ashton, which aims to integrate up to 50,000 ethnic Serbs with the rest of Kosovo.

Officials are weighing whether to repeat the vote in the Serbian stronghold of north Mitrovica where the violence erupted. Serb hardliners are strongly opposed to the pact and tried to intimidate Serb voters into boycotting the ballot.

Ashton said in a statement she would host Serbian Prime Minister Ivica Dacic and his Kosovo counterpart Hashim Thaci. Officials said the meeting had been planned before the election.

"(The leaders will discuss) the next steps in the electoral process as well as the next steps in the implementation of the April Agreement," Ashton said in the statement, which described Sunday's vote as "crucial for Kosovo's future".

Kosovo declared independence from Serbia in 2008, almost a decade after a 1998-99 war ended in 11 weeks of NATO bombing to halt the massacre of Albanians by Serbian forces. They had been trying to crush a two-year insurgency in Serbia's then-province.

Serbia retained de facto control over Serb northern Kosovo, but agreed to cede it in April in return for EU accession talks - expected to begin in January - and the economic boost Belgrade hopes that process will bring.

EU election observers described Sunday's vote as a "positive step forward for democracy" despite the violence.

"The fact that people did go to vote demonstrates that those who wished to sabotage the process have failed," chief observer Roberto Gualtieri told a news conference in Pristina on Tuesday.

Political sources said NATO peacekeepers and EU and Kosovo police would need to stage a more robust security operation to deter violence if the poll were repeated in the Serbian region. (Additional reporting by Luke Baker/Adrian Croft in Brussels; Writing by Matt Robinson, Editing by Gareth Jones)

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