In January 1990, together with
Adrian Dimitriu (the former secretary general of the Independent Social Democratic Party) chaired by
Constantin Titel Petrescu), Mira Moscovici, Constantin Avramescu, Mircea Iscru Stanescu (the veterans of the old party active in 1946) they established the new PSDR party. The PSDR claimed to be the legitimate and unique successor of the Independent Social Democratic Party (PSDI) and, together with the
Christian Democratic National Peasants' Party (PNȚ-CD) and
National Liberal Party (PNL), parties established in 1990 also claiming the legacy of pre-1948 parties, formed the political opposition against the ruling
National Salvation Front (FSN). In 1990–2000, Cunescu was the chairperson of the PSDR. In 1992 and in 1996, he was re-elected within the Congresses. In 1990–2000, he was a member of the
Romanian Parliament, being a parliamentary group leader. In 2000, at the party's Congress, which by that time had merged with the Socialist Party led by
Tudor Mohora,
Alexandru Athanasiu was elected as an executive chairperson, and Sergiu Cunescu became the honorary chairperson of the party. In 2000, he resigned from the position and left the party. His resignation came shortly after merging by absorption of PSDR by PDSR, the former FSN, which became the
Social Democratic Party (PSD). Cunescu succeeded to join the PSDR to the
Socialist International. Initially an observer party and afterwards with the a consultative role, the party eventually became a full-fledged member. Sergiu Cunescu was a supporter of modern social democracy, of the Franco-German origin, mastering
Bad Godesberg’s reformist theses, who delineated the European left-wing movement of Marxism. Among his most important comrades were Radu Dimitrescu, Constantin Avramescu (until 1997), Smaranda Dobrescu, etc. On 16 March 2005, Cunescu died, at age 82. In 2006, in memory of his conceptions, democratic principles and social solidarity the book “Social Democracy, Illusion and Reality” by Smaranda Dobrescu was published by Niculescu Publishing House. He is buried in the Cunescu family's cave at the Orthodox
Bellu Cemetery. ==References==