Madhesi parties demanding autonomy for the Terai region dominated by the Indian-origin community stalled Parliament proceedings for the fourth straight day on Monday putting a spoke on the formation of Nepal's first Maoist-led Government.The Parliament needs to pass an amendment allowing formation of government with a simple majority instead of the current two-thirds required to pave the way for Maoists to come into power.Madhesi Constituent Assembly members raised slogans and surrounded the rostrum to disrupt proceedings prompting Chairman K B Gurung to adjourn the House till Tuesday, said Rajendra Mahato, president of Sadbhavana Party.The Madhesi People's Rights Forum, Terai Madhesh Lokatantrik Party and Sadbhavana Party, the three pro-Madhesi organisations which form the fourth biggest group in the 601-member Assembly, are demanding that the constitution be amended to create a single autonomous region in the Terai plains.The Madhesi demand has been outrightly rejected by the country's three main parties- Nepali Congress, CPN (Maoist) and the CPN (UML)."Unless the government agrees to incorporate in the constitution our demands of declaring Madhes as an autonomous region and group inclusion of Madhesis in the national army, we will not allow the amendment of the statute to facilitate the formation of the Maoist led government," Mahato, a Madhesi leader, said.The Maoists led by Prachanda have just 220 seats in the Constituent Assembly. The three main parties had failed to agree on power sharing despite protracted negotiations dampening hopes of formation of a unity government.