The announcement was made after a meeting in New Delhi of the leaders of the parties including JD-United, Left, Samajwadi Party, All India Anna Dravida Munnetra Kazhagam.
However, the ticklish issue of their prime ministerial candidate was put off till after the elections. Addressing a press conference after the hour-long meeting, Communist Party of India-Marxist general secretary Prakash Karat said the 11 parties will work together to defeat UPA whose rule has witnessed massive corruption and price rise.
Flanked by Janata Dal-United leader and Bihar Chief Minister Nitish Kumar, SP chief Mulayam Singh Yadav, JD-S leader H D Deve Gowda and some others, Karat said BJP's policies are similar to those of Congress. "The BJP is the other side of the same coin," he said.
Moreover, the BJP represents communal politics which is dangerous for the country, he added.
The 11 parties will present an alternative to the UPA and the BJP, said the CPI-M leader.
He appealed to other "secular" parties to join them in their endeavour. Mulayam Singh said the third alternative grouping could expand in future. "Today, we are 11 parties, it can be 15 parties later," he said.
Asked whether the JD-U will again re-align with the BJP if the third alternative experiment does not work, Nitish Kumar asserted that he will have "no contact, leave alone the question of returning to the BJP".
The meeting was also attended by Deve Gowda JD-Secular, veteran CPI leader A B Bardhan, M Thambidurai (AIADMK), T G Chandrachoodan (Revolutionary Socialist Party), Debabrata Biswas (Forward Bloc), Sitaram Yechury (CPI-M), K C Tyagi (JD-U), S Sudhakara Reddy (CPI).
However, representatives of Asom Gana Parishad (Asom Gana Parishad) and the Biju Janata Dal were conspicuous by their absence, though Karat said the chiefs of both these parties -- Prafulla Kumar Mahanta and Odisha Chief Minister Naveen Patnai had expressed support to the initiative.
To questions on seat sharing or alliances among these parties in the upcoming polls, Karat said, "Every party has strength in its own areas and states. We will pool our resources at the all-India level after the elections."
This does not necessarily mean that all these parties would enter into alliances or go for seat adjustments in all states for the upcoming general elections, he said.
Asked whether the JD-U will again re-align with the BJP if the third alternative experiment does not work, Nitish Kumar asserted that he will have "no contact, leave alone the question of returning to the BJP".
The joint declaration said the leaders of the 11 parties have resolved to work together for strengthening the democratic framework, ending corruption and ensuring accountability in government.
In an apparent reference to the BJP, it said the parties would establish "a firm secular order which recognises the plurality and diversity of our society".
They also promised to provide "a people-oriented developmental path which addresses the concerns of inequality, social justice, farmers' interests, minorities and women's rights".
The parties spoke of reversing the centralising model at the Centre, creating a true federal system so that all states' rights are assured, including special category status for states which deserve it.
The rainbow coalition appealed to other secular democratic parties and all sections of the people to support the principles set by them.
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