* EU foreign policy chief to go to Montenegro, Albania and Macedonia
* EU due to issue report on Tuesday on Serbia and Macedonia
* Serbia's hopes of starting EU talks hurt by rejection of Kosovo pact
European Union foreign policy chief Catherine Ashton will visit the Western Balkans this week, when the European Commission is due to decide whether to recommend the start of EU membership talks with Serbia and possibly Macedonia.
Ashton's trip will take her to Montenegro, Albania and Macedonia, an EU statement said on Sunday. It said further stops on the tour would be announced later, leaving open the possibility that Serbia could be included.
"I travel to the Western Balkans to reinforce the EU's commitment to the European perspective for the countries in the region. I will encourage the leaders in the region to continue the reform process and promote good neighbourly relations," Ashton said in the statement.
The European Commission, the EU's executive arm, is expected to issue a progress report on the Western Balkans on Tuesday, when it will decide whether to recommend the start of accession talks with Serbia and possibly Macedonia. The report is also expected to cover Kosovo's prospects for a closer relationship with the EU.
Serbia's rejection this month of an EU-brokered plan to tackle the ethnic partition of its former province of Kosovo was a setback to Belgrade's hopes of starting membership talks.
However, Serbia's coalition government called last week for the urgent continuation of negotiations on Kosovo, chaired by Ashton, and a Kosovo government adviser has said there could yet be one more push for an agreement before the EU releases its report.
Kosovo broke away from Serbia in a 1998-99 war and declared independence in 2008.
The West wants Belgrade to cede its fragile hold on a northern, Serb-populated pocket of Kosovo, where ethnic Albanians are the 90-percent majority - an ethnic partition that frequently flares into violence and has frustrated NATO plans to cut back its now 6,000-strong Kosovo peacekeeping force.
In a U-turn, Serbia has offered to recognise the authority of Pristina over the entire territory of Kosovo, but wants broad autonomy for the 50,000 Serbs living in the north.
Croatia, Serbia's wartime foe during the collapse of Yugoslavia, is set to become the EU's 28th member on July 1, joining Slovenia which is already part of the club.
Montenegro has begun talks on joining the EU and Macedonia, like Serbia, is a candidate for membership.
However, Macedonia's efforts to join the EU and NATO have been blocked by a dispute with neighbouring Greece over Macedonia's name, which it shares with a northern Greek province. Greece wants it changed.
Albania has so far been denied EU candidate status because of its failure to pass necessary legislation, while Kosovo has yet to apply for accession.
EU enlargement commissioner Stefan Fule said last week that Bosnia's bid to join the EU faced being "frozen" and a planned election next year declared invalid without urgent reform of its constitution.