Kolkata (PTI): West Bengal Chief Minister Buddhadeb Bhattacharjee on Wednesday said that Prime Minister Manmohan Singh was responsible for breaking the UPA coalition which had resulted in withdrawal of Left support to the government.

Speaking at the condolence meeting of former CPI-M general secretary Harkishan Singh Surjeet here, Bhattacharjee said that the Left's support to UPA government was not unconditional.

"We had been opposing the 123 deal as it would undermine the country's sovereignty," he said.

He said that the Prime Minister had broken the coalition by trying to enter into the civil-nuclear deal with the US.

The Left parties are in such a situation now that they have to ward off dangers posed by the Congress on one side and BJP on the other. "In this scenario, we will have to build up a separate front," he said.

Referring to BJP, he said that although the party was not in power, it was trying to raise its `ugly head' as manifested in the recent violence in J&K and Orissa.

Recounting Surjeet's contribution to coalition politics, he said that the Left parties should garner enough strength to fight communal forces.