The controversial bill would strip dozens of deputies of their parliamentary immunity, with pro-Kurdish deputies saying is directly aimed at driving them out of the legislature

The Turkish parliament on Tuesday begins debating a hugely controversial bill that would strip dozens of deputies of their parliamentary immunity and which pro-Kurdish deputies say is directly aimed at driving them out of the legislature.

The bill has already led to unprecedented scenes at the committee stage with deputies exchanging angry blows with their fists and even feet rather than discussing the document.

The debates, which could prove fiery, are to begin at around midday GMT in the main chamber, with a final vote expected on Friday.

Under current Turkish law, MPs in parliament have the right to full immunity from prosecution. If passed, the bill would lift the immunity of 130 deputies from all parties whose dossiers have been sent to the parliament speaker.

But the pro-Kurdish Peoples' Democratic Party (HDP) says the bill is essentially a drive to expel its MPs from parliament.

HDP MPs are particularly vulnerable to prosecution on allegations of links or even verbal support for the outlawed Kurdistan Workers Party (PKK), which is fighting a renewed insurgency against the Turkish state.

"What this motion seeks to destroy is the HDP in parliament," party co-leaders Selahattin Demirtas and Figen Yuksekdag, both of whom could face prosecution, said in a letter to European MPs.

Should a number of HDP deputies leave parliament, it would ease the path for President Recep Tayyip Erdogan to realize his dream of changing the constitution to create a presidential system in Turkey.

"If successful, this coup would be a most crucial step for Erdogan to replace Turkey's parliamentary democracy... with an absolutist presidential system."

Should the bill become law, it raises the prospect that the likes of Demirtas and Yuksekdag -- already the target of criminal investigations -- could go on trial on charges of making "terrorist propaganda" for the PKK and even face time in jail.

The ruling Justice and Development Party (AKP) will be able to push the bill through if it wins the support of the Nationalist Movement Party (MHP) -- which despises the HDP -- and some MPS from the main opposition Republican People's Party (CHP).