Four volatile regions of Tunisia -- including the part of the country where the Arab Spring began -- went on strike on Thursday, amid rising tensions with the country's ruling Islamist party.

As well as Sidi Bouzid, where the uprising started two years ago that unseated former dictator Zine El Abidine Ben Ali and was emulated in other Arab countries, the strike was followed in the regions of Kasserine, Gafsa and Sfax, whose eponymous capital is Tunisia's second city.

The closure of the main private and public companies in those areas was called by regional branches of the country's main labour group, the General Union of Tunisian Workers (UGTT). Demonstrations were expected later in the day.

Only small shops and cafes were open for business.

Thursday's strike was seen as a prelude to the nationwide general strike called for December 13 by the UGTT to denounce an attack on its headquarters earlier this week that it says was carried out by Islamist militants close to the Ennada ruling party.

The nationwide strike call is only the third to be made by the powerful UGTT, with its membership of 500,000, since its foundation in the 1940s. It is a sign of the deep divisions between Tunisia's secularist and Islamist factions.

The first strike was in 1978 and the second on January 12, 2011 -- two days before the fall of Ben Ali's regime.

Clashes, strikes and attacks, including by hardline Islamists, have multiplied across Tunisia in the run up to the second anniversary of the revolution, plunging the country into a political impasse.

Many Tunisians feel bitterly disappointed by the failure of the revolution to improve their lives, especially in the country's marginalised interior, which suffers from a chronic lack of development and high unemployment.