New Delhi, Aug 20 - Former union minister Jaswant Singh Thursday said the Bharatiya Janata Party (BJP) leadership should have clarified which reference to Sardar Patel in his book on Mohammed Ali Jinnah aggrieved them so much that he was expelled from the party.

Singh, who returned to Delhi from Shimla after his expulsion, told reporters: 'There is a mention of Sardar Patel some seven to eight times in the book. I don't know which particular part aggrieved the party. They have not clarified, they have still not clarified this.'

He said he wished his former party colleagues had read the book, which was not against Sardar Patel but said the Congress and the British were also responsible for the partition of India.

Singh wondered what happened between the 'evening of 17th (when the book was released) and 1 p.m. on 19th' when he was expelled.

The 71-year-old leader said the fact that he was writing a book on Jinnah was not hidden from the party leadership.

'I had mentioned at the launch of Lalji Advani's book launch that I am writing a book on Jinnah. They asked me can you withhold the book till the assembly elections (in November and December),' he said, adding that then the leadership wished he put it off till the Lok Sabha elections.

Later, the party expected him to release the book after the three-day chintan baithak (brainstorming meeting) that began in Shimla Wednesday.