"There will be no contact group meeting today," Belarussian foreign ministry said spokesman Dmitry Mironchik told AFP by telephone.
The so-called Trilateral Contact Group on Ukraine also includes mediators from Russia and the Organization for Security and Co-operation in Europe (OSCE).
The warring sides reported a tense day of inital negotiations on Wednesday that made little progress toward a final peace accord.
The ministry spokesman added that "Belarus is always ready to offer (Minsk) as a negotiations venue."