German Foreign Minister Frank Walter Steinmeier summoned the Ukrainian ambassador on Friday to express concern over violent clashes between protesters and police, said Steinmeier's spokesman. Concern was also voiced over more stringent laws governing freedom of assembly and the treatment of non-governmental organizations. The recent intervention serves as a signal to Ukrainian leaders "that we are serious about it," the spokesman said. On Thursday, German Chancellor Angela Merkel spoke to Ukranian President Viktor Yanukovych over the telephone, advising him against suppressing peaceful protests and to have a serious dialogue with the opposition. Demonstrations erupted in Kiev in November after Ukraine backtracked on a partnership agreement with the European Union, a path toward a membership of the bloc. At least two demonstrators were shot dead in Kiev on Wednesday during clashe. .