German Chancellor Angela Merkel (CDU) has expressed sadness at the unexpected death of leading Social Democrat Party (SPD) lawmaker Thomas Oppermann.”For many years I have valued him as a reliable and fair social democratic partner” in her coalitions with the SPD, her spokesman Steffen Seibert quotes her as saying.As a parliamentary group leader, Oppermann had “rendered outstanding services to our parliament in turbulent times,” Merkel said.