Feeling "insulted" by Prime Minister Manmohan Singh, opposition National Democratic Alliance decided to boycott proceedings in Parliament on Thursday.
The decision was taken at a meeting of NDA allies in Delhi.
BJP Parliamentary Party spokesman V K Malhotra told reporters after an hour-long meeting that the primeminister had called up Jaswant Singh and L K Advani, Leaders of Opposition in Rajya Sabha and Lok Sabha respectively.
Without divulging details of the conversation, he said, "It was not satisfactory."
NDA sources said Singh conveyed to the Leaders of Opposition that he did "not intend" what was perceived about his behaviour and there should be an attitude of "forget and forgive".
"But we want the prime minister to express public regrets over his attitude," they said.
"All NDA leaders are upset at the 'shocking attitude' of the Prime Minister meted out to an NDA delegation when it met him yesterday," Malhotra said.
"The Prime Minister's attitude amounted to an insult to the Opposition as well as democracy," he said.
He said the opposition was also peeved at the Congress for "justifying" the Prime Minister's behaviour "instead of amending things and taking corrective steps."
NDA's members of Parliament will meet here tomorrow again to chalk out future course of action.