The head of Italy's anti-establishment 5-Star Movement Beppe Grillo urged police on Tuesday to join protesters as a wave of "pitchfork" protests gave vent to bitter frustration after years of austerity and recession.

The "pitchfork movement", originally a loosely organized group of farmers from Sicily, has been joined by other protestors including truckers, small businessmen, the unemployed, low-paid workers and others who have staged rallies in cities from Turin in the north to Sicily in the south.

Grillo, whose movement has no direct connection with the protests, welcomed reports that several police officers took off their riot helmets and expressed sympathy with demonstrators on Monday.

"Italians are on your side. Join them. At the next demonstrations, tell your guys to take off their helmets and fraternize with the citizens," he wrote on his popular blog. "It will be an extreme, peaceful and revolutionary signal and Italy will change," he wrote.

Though there are no direct ties to Grillo's movement, both tap into the growing anger in many parts of Italy after the worst recession in postwar history.

Apart from demanding the government be replaced and parliament dissolved, the precise targets of the protests remain vague, ranging from tax collection agency Equitalia and high fuel prices to privileged elites and the euro.

Protests on Monday were marked by a number of clashes with police, who fired teargas but there were no reports of serious trouble on Tuesday.

A confidence vote in parliament on Wednesday, called by Prime Minister Enrico Letta to confirm his parliamentary majority after Silvio Berlusconi's Forza Italia party left the ruling coalition, may provoke further tensions.

"If the government wins the confidence vote on Wednesday and the politicians remain in place, all the pitchforks in Italy will move on Rome for a peaceful invasion," Danilo Calvani, one of the organizers, told the daily Corriere della Sera.

His remarks were later contradicted by other members of the movement, leaving it unclear whether there would be any direct reaction to Wednesday's vote, but they underlined the tense climate facing the government as it seeks to push on with economic reforms.

Italian media reported that the "pitchfork movement" was backed by political groups including the hard-right Forza Nuova party but organizers denied any political links.

"This is a movement of Italian people and that's it. We dissociate ourselves completely from these extremist parties like Forza Nuova, which actually favor the system with the things they say," Calvani said.

Letta has warned repeatedly that opposition to the government and the EU is growing strongly, fuelled by sacrifices needed to keep public finances in order and which could result in a massive anti-EU vote in next year's European parliamentary elections.