"I am giving two gifts (pen and broom). You all should decide which one could eradicate sins in the society and which reminds you that you can not treat the society only by slogans," he said.
Khan's gift is seen as a covert attack on Modi, who has given the slogan for 'Swacch Bharat Abhiyan'.
The minister, earlier during the session, had attacked the PM on the issue by saying that he had given broom in people's hand and took away pen from them.
The strolley bag, carrying pen, broom and his letter, was sent to legislators after the end of assembly session on March 26.
In the letter to the mnembers of Legislative Assembly, Khan also said: "You have seen and tested me. I am not the one what people say, but the one whom your heart knows. I know you are truthful and realise truth.
Commenting on the 'gifts', Bharatiya Janata Party legislator Radha Mohan Das Agarwal said PM had given a good message in the society by launching the cleanliness drive, which he (Azam) could not digest.
"By gifting broom he has only propagated the ideology of the PM," Agarwal said.
Bahujan Samaj Party legislator Ram Prasad Chowdhury said that he had received the 'gift' but he did not see the letter till now as he had left for his constituency after the session was over.
The Congress has termed the 'gift' as an admission of tacit understanding between the SP and the BJP. "The gift is an admission of an understanding between the SP and the BJP. It seems that he has tried to disclose the understanding in indications by giving a broom with pen," Congress legislator Nadeem Javed said.
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