Moscow, Shawwal 08, 1436, July 24, 2015, SPA -- The leaders of Russia, Ukraine, France and Germany held a conference call late Thursday to discuss efforts to resolve the conflict in eastern Ukraine, according to statements by their offices, dpa reported. Ukrainian President Petro Poroshenko said the security situation in the region was "deteriorating" with "increasing attacks by militants," according to a statement on his website. In their phone call, the four leaders noted importance of the OSCE's role in monitoring of the conflict, according to the statements. The Kremlin's statement particularly noted that the leaders "expressed satisfaction" with two major separatist groups' announcement "to carry out a voluntary and unilateral withdrawal of arms of a calibre of less than 100 millimetres." --SPA 14:31 LOCAL TIME 11:31 GMT www.spa.gov.sa/w