ATHENS (Reuters) - Greece’s parliament has no jurisdiction to investigate the role of ten politicians in alleged bribes by Swiss drugmaker Novartis, lawmakers ruled on Saturday, in a controversy which has further polarized a deeply divided political landscape.

FILE PHOTO: Greek Prime Minister Alexis Tsipras addresses lawmakers as Parliament Speaker Nikos Voutsis (top C) chairs a parliamentary session before a vote on setting up a special committee which will probe the role of ten politicians in a case which involves alleged bribery by Swiss drugmaker Novartis, in Athens, Greece, February 22, 2018. REUTERS/Alkis Konstantinidis/File Photo

Greek prosecutors were probing allegations from three individuals suggesting doctors and public officials had accepted kickbacks in a period spanning 2006 to 2015.

Ten public officials who served under socialist and conservative governments over that period say the allegations, which they denied, was a ‘sick’ mud-slinging campaign fabricated by the leftist-led government.

The administration, forced to sign up to a third international debt bailout in 2015, is trailing badly in opinion polls ahead of elections scheduled in 2019.

The majority of the lawmakers that were present in the parliament, 168 out of 172, voted against the investigation. The main opposition party, the conservative New Democracy, abstained from the voting process.

Greek ministers are protected from prosecution if the alleged offense was committed while in office. Under Greek law, parliament is the only institution that can investigate them or lift their immunity.

“The dead-ends you led the country to are so nightmarish you needed made-up victims to slur, and divert attention of the public to them so it wouldn’t see your own dismal failures,” said former Prime Minister Antonis Samaras, among those investigated.

Novartis itself has said it would take “fast and decisive action” should evidence of unethical or illegal behavior emerge.

Greek Prime Minister Alexis Tsipras had urged parliament to investigate the case, but an investigating committee, dominated by lawmakers from his own Syriza party, subsequently decided it had no jurisdiction last month. That decision followed blanket media coverage of the alleged allegations.

Some of those politicians said the decision not to investigate was a cop-out to avoid a thorough probe which would have exonorated them, and that it was an attempt to throw enough mud to see if it would stick.

“These un-investigated slanders have created a sick environment for some to play cheap political games where no rules apply, at the expense of the honor and dignity of those who are being slandered, and, worse of all, to the detriment of justice and democracy,” said Yannis Stournaras, a former minister and present head of Greece’s central bank.

Novartis has in the past said it was cooperating with Greek and U.S. authorities, but it said publicity around the case included ‘many sensational and unfounded claims’ in a politicized debate of which Novartis should not be a part of.

Since 2015, Novartis has paid out hundreds of millions in settlements and fines as a result of kickback allegations inSouth Korea, the United States and China.