The Serbian and Kosovar prime ministers are due to meet under European Union mediation to discuss implementation of the accord to normalize relations between Serbia and Kosovo.
The May 21 talks in Brussels bring together Serbian Prime Minister Ivica Dacic and his ethnic Albanian Kosovo counterpart, Hashim Thaci.
German Foreign Minister Guido Westerwelle hailed the April 19 agreement as "historic" but called for "concrete steps" to implement it.
Westerwelle on May 20 visited the region and met with Dacic and Thaci.
The European Union has made progress on implementing the pact a condition for Serbia to start EU membership negotiations.
The EU is expected to decide on Serbia’s bid at the end of June.
Kosovo's minority Serbs reject the 2008 declaration of independence from Serbia by Kosovo's ethnic Albanian leadership.
Based on reports from dpa and AFP