In October 2004, Kassar was appointed minister of economy and trade in the cabinet led by prime minister Omar Karami, replacing Marwan Hamadeh as economy minister.
He was elected since 1992 member of the Lebanese Parliament represented the Greek Orthodox seat from Marjeyoun-Hasbaya district and has been named repeatedly to the government: Minister of State without portfolio between 1990 and 1992 (government of Omar Karami and Rachid Solh), Minister of Labour between 1995 and 1998 and between 2003 and 2004, he was succeeded by Assem Qanso in 2004.
Saba was among the politicians who joined former Prime Minister Omar Karami in creating the Rassemblement national in 2006.
In the post-Taif period Sassine was appointed Vice-Prime Minister and Minister of Labor in both the 1990-1992 governments of Salim al-Hoss, and Omar Karami.
Just before his arrest in August 2012, he was a member of Omar Karami’s pro-Syrian movement, the National Gathering.
His youngest daughter Leila Al Solh Hamade was appointed as one of the first two female ministers in Omar Karami's government.
Omar Sharif | Omar Khadr | Don Omar | Omar Bradley | Rubaiyat of Omar Khayyam | Omar Khayyám | Omar Karami | Omar Rodríguez-López | Omar | Omar al-Bashir | Omar Abdel-Rahman | Ahmed Omar Abu Ali | Omar Suleiman | Omar Epps | Omar Barghouti | Omar Ayub Khan | Omar Ahmad Omar al-Hubishi | Mohammed Omar | Misha Omar | Abu Omar al-Kurdi | Said Ali bin Said Omar of Grande Comore | Omar Vizquel | Omar Sy | Omar Sívori | Omar Lye-Fook | Omar Little | Omar Khyam | Omar Khayyam | Omar Khan | Omar Faruk Tekbilek |
Following the resignation of the government of Omar Karami in May 1992, President Elias Hrawi was forced to form a new government and to hold the first parliamentary elections since the end of the civil war.