Congress vice president Rahul Gandhi on Sunday said the success of the Grand Alliance in Bihar was a victory against the RSS, the BJP and Prime Minister Narendra Modi.

"This is not a victory against NDA, but against RSS, BJP and Modi. It is a message against dividing Hindus and Muslims," a smiling Gandhi told reporters.

He also congratulated Bihar Chief Minister Nitish Kumar and Rashtriya Janata Dal (RJD) leader Lalu Prasad over the victory. The Congress party was in alliance with the Janata Dal-United and RJD for 243 seats in the eastern state.

The BJP-led coalition's defeat in Bihar was a referendum on Prime Minister Narendra Modi's working style, Delhi Chief Minister Arvind Kejriwal said on Sunday.

"The results are a referendum on the work and working style of Modi," the Aam Aadmi Party (AAP) leader told the media here.

He also said that the sweeping win by the ruling Janata Dal-United (JD-U) and its allies RJD and Congress had shattered the "arrogance" and "self pride" of Modi and BJP president Amit Shah.

"The Bihar results have proved that people do not approve of the politics of hatred.

"An atmosphere of intolerance had enveloped the entire country. I am hopeful that all this will stop and the politics of affection will start."

The BJP's Bihar defeat marks the beginning of the downfall of the Narendra Modi government, Kerala Chief Minister Oommen Chandy said on Sunday.

Chandy telephoned Bihar Chief Minister Nitish Kumar, RJD chief Lalu Prasad and Bihar state Congress president Ashok Choudhary and congratulated them on their thumping win in the assembly elections.

"Modi's strategy of dividing people on communal and divisive lines has fallen flat. The beauty of Indian democracy is its unity in diversity, and Modi has played spoilsport. His government has now become a liability for the country," a statement from Chandy said.

He also hit out at the CPI-M led Left for failing to back the Grand Alliance in Bihar.

"In Delhi and in Kerala the CPI-M breathes fire against the BJP. But in Bihar, they contested the elections alone to split the secular votes so as to help the BJP," said Chandy.

MIM chief Asaduddin Owaisi on Sunday said the Bihar assembly elections result is a personal defeat of Prime Minister Narendra Modi.

"It's a personal defeat of Modi as never before a prime minister campaigned so much in an election," said the Majlis-e-Ittehadul Muslimeen chief, whose party contested six of the 243 constituencies but drew a blank.

"Never before in the history of independent India, we had seen a sitting prime minister getting so involved and addressing more than 35 public meetings," the Hyderabad MP told reporters at Darussalam, the MIM headquarters.

Stating that people of Bihar have given decisive mandate against communalism and fascism, he said: "The atmosphere in Bihar was that Modi should be defeated. Muslims and other communities had decided to defeat Modi."