Karnataka's former chief minister S Bangarappa, who quit the Bharatiya Janata Party earlier this week, resigned his Lok Sabha seat on Thursday and joined the Samajwadi Party as its Karnataka unit president.

Bangarappa, 72, joined the BJP ahead of the Lok Sabha elections. He won the Shimoga seat in Karnataka in the polls.

Speaker Somnath Chatterjee announced in the Lok Sabha ahead of the Question Hour that he had received a resignation letter from Bangarappa. "His resignation has been accepted," Chatterjee said.

After resigning his Lok Sabha seat, Bangarappa joined the SP in New Delhi in the presence of its president and Uttar Pradesh Chief Minister Mulayam Singh Yadav.

Announcing his intention to join the Samajwadi Party last month, he had said, "I entered Karnataka Legislative Assembly in 1972 as a socialist, and now [have] decided to join the SP, which is also working on the same principle of socialism."