The Bharatiya Janata Party and its National Democratic Alliance allies will boycott the swearing-in ceremony of Congress president Sonia Gandhi as prime minister, BJP president M Venkaiah Naidu said in New Delhi on Monday.

Naidu, who was accompanied by NDA convener George Fernandes, said the outgoing Prime Minister Atal Bihari Vajpayee would, however, attend the ceremony "keeping with the tradition".

"We will be abstaining from the swearing-in ceremony to express the people's sentiment," he said.

Naidu also said the party would not launch any specific agitation on Gandhi's foreign origin issue and "we will fight it out both inside and outside Parliament. We will play the role of a constructive opposition".

He said, "There is no question of boycotting this government."

Asked about BJP leader Sushma Swaraj's decision to quit the Rajya Sabha, Naidu said the issue was discussed in the meeting. The party was of the opinion that it was an individual decision.

"We are not going to leave this issue. We are going to keep this alive," Naidu said.