Golden Dawn MP Ilias Kasidiaris starts a brawl on a TV talkshow with fellow politicians. Source: YouTube/hellenicbusiness YouTube/hellenicbusiness

Greece's pre-electoral climate has become more explosive after a high-profile neo-Nazi MP assaulted two female politicians from leftwing parties on live TV. The brawl, a first in the nearly 40 years since democracy was returned to its birthplace, broke out during a morning talkshow when Ilias Kasidiaris, the spokesman of the far-right Chrysi Avgi (Golden Dawn) took umbrage at deputy Rena Dourou declaring that his party "will take the country back 500 years".

After leaping from his seat and throwing a glass of water at Dourou, a deputy with the radical Syriza party, Kasidiaris then turned on Liana Kanelli, an MP with the KKE communist party, who, waving a piece of paper, stood up to condemn the action.

As the cameras rolled, the cropped-haired Kasidiaris, a weightlifting enthusiast, who had served in the Greek military's special forces, is shown lashing out at Kanelli slapping her around the face three times as she threw up her arms in self-defence. Shouting :"No, no, no," the talkshow's presenter, Giorgos Papadakis, then tried to intervene but within moments other guests present said the MP had fled the studio.

The extraordinary footage quickly prompted state prosecutor Eleni Raikou to order the immediate arrest of Kasidiaris. The 31-year-old, who was elected to the 300-seat Athens parliament in the country's inconclusive election last month, is the most vocal opponent of suggestions that Chrysi Avgi is a violent organisation with a history of attacks on society's most vulnerable not least Greece's burgeoning population of immigrants.

By early afternoon, the neo-fascist party had refused to condemn the incident despite Dimitris Tsiodras, a spokesman in the interim government, describing it as "an attack against every democratic citizen".

Despite Kasidiaris's denials of Golden Dawn's links to such unsavoury practices, he is no newcomer to charges of violence himself. On Monday the party's spokesman appeared in court accused of aiding and abetting an armed robbery in which a postgraduate student was savagely stabbed in 2007. The trial was postponed until 11 June.

Thursday's incident will throw further light on the extremist group catapulted into parliament with almost 7% of the vote on a wave of anti-austerity anger in a nation attempting to keep bankruptcy at bay for nearly three years. Its capture of 21 seats for the first time since the collapse of military rule in 1974 sent shockwaves through Europe.

In a country where it is common for people to shout but almost never engage in fisticuffs, the punch-up played over and over again on TV channels, has been met with outrage by parties across Greece's normally divisive political scene.

Prokopis Pavlopoulos, a former conservative New Democracy minister also participating in the talkshow, said Kasidiaris's thuggish behaviour should leave Greeks in "no doubt" as to the true nature of Chrysi Avgi.

"Now that they have seen what this party is really about, Greeks will have no alibi to vote for them again," said the veteran conservative. "I, personally, will never take part in a debate with a member of Chrysi Avgi again."