Action against Lok Sabha Speaker Somnath Chatterjee [Images] was decided well before the trust vote, but was not announced lest it should affect discussion over issues that prompted the party to withdraw support to the UPA Government, Kerala [Images] Chief Minister V S Achuthanandan said.

Chatterjee's defiance of the party line was a clear and conscious violation of the organisational discipline by a person who was aware of these things, the veteran Marxist leader told reporters in Thiruvananthapuram.

"We refrained from disclosing our decision before the trust vote was taken up in Parliament on the premise that it should not deflect attention from the basic issues to be debated by the House," Achuthanandan said.

Chatterjee was expelled from the party by the poliutburo for defying its directive to step down.

Achuthanandan said though the UPA won the trust vote he saw it as a victory clinched through "unethical means".

He said it was the duty of his party and the Left bloc as a whole to oppose the nuclear deal since "it amounted to abject surrender to the American imperialism".

The coming days would show how those who had helped the government to survive the confidence vote were going to bargain for the "services" they had extended, he added.

Earlier in the day, Kerala CPI-M secretary Pinarayi Vijayan lashed out at Chatterjee for his defiance of the party line. Vijayan branded him as a 'betrayer'.

"Chatterjee has betrayed the party in which he had held high positions. His place in history will be that of a betrayer of the party", Vijayan said.