Expelled BJP leader Jaswant Singh today rejoined the party nine months after he was summarily thrown out for writing a controversial book on Pakistan founder Mohammed Ali Jinnah.

At a function organised to announce his re-induction into the party fold, 72-year-old Singh profusely thanked senior BJP leader L K Advani for taking the initiative to bring him back to the BJP of which he was a founder member.

"It is good to be back in familiar surroundings... I wish to unreservedly express my gratitude to Advaniji who took the initiative," Singh said. Among others present were party president Nitin Gadkari and Leader of the Opposition in Lok Sabha Sushma Swaraj.

Recalling his expulsion from the party at its 'Chintan Baithak' in Shimla in August last year, the MP from Darjeeling said, "I was hurt and humiliated by what I had encountered."

Advani said he was "very happy" that Jaswant Singh, whom he had met as an RSS pracharak in Rajasthan, has rejoined the party.

"I am very happy. With happiness there is also a sense of relief. I welcome him," he said.

Gadkari said the "past is past" and hoped that Singh will work to make the party's future bright.

He said this was a day of "great happiness" for him and the party workers.

Singh was expelled from the BJP in August 2009 for praising the Pakistan founder in his book "Jinnah - India, Partition, Independence".

While holding Jawaharlal Nehru and Sardar Patel responsible for partition, Singh maintained that Jinnah was secular, a position that was unacceptable to the Sangh Parivar. Gujarat Chief Minister Narendra Modi had banned Singh's book in his state.

After his expulsion, BJP also asked Singh to step down from the Chairmanship of Parliamentary Public Accounts Committee but he refused. He gave up the post in December last year.