Dissanayake, who is also a legislator from the main opposition United National Party, was escorted to prison shortly after Chief Justice Sarath Silva read out the verdict after a lengthy trial.

Dissanayake led a split that saw the collapse of SLFP-led government

No appeal is possible against a Supreme Court verdict.

Under Article 89 of the Constitution, any person who is serving or has served a jail term of more than six months disqualifies to be an elector for a period of seven years.

Dissanayake was initially a staunch loyalist of President Chandrika Kumaratunga, but fell out of favour in 2001 and led a split that saw the collapse of her government.

He also had a reputation of running election campaigns with enthusiasm.

SB Dissanayake made the offending statement about the Supreme Court judges, while he was a minister in Prime Minister Ranil Wickremesinghe's United National Front cabinet.

He was charged with making a speech at a “Wap Magul” ceremony in southern Sri Lankan town of Habaraduwa in November last year in which he was alleged to have defamed the Supreme Court and judges.

It was an unusually severe penalty for contempt of court in Sri Lanka. SB Dissanayake was a senior member of the Peopels Alliance. Since he had crossed over, he became one of the fiercest critics of the president and her ruling coalition.

In a recent statement, President's brother, and a former colleague of SB Dissanayake, Anura Bandaranayake made a public statement assuring that he will be sent to jail.