Mann, who was shouting slogans in the Well, felt uneasy and was apparently looking for water on the table of Lok Sabha secretariat officials who sit in the Well.
A smiling Modi offered him the glass of water kept on his table which the AAP member readily drank. The two exchanged smiles before Mann kept the glass on the table and the PM put the cover on it. Several Bharatiya Janata Party members thumped their desks at the PM's gesture.
Mann, thereafter, continued to raise anti-government slogans.
Mann, along with several Congress members, were protesting inside the Well soon after the Speaker disallowed their notices of motions to adjourn the Question Hour on various issues including role of Arunachal Pradesh Governor. The Question Hour continued amidst the din.
The AAP member from Sangrur constituency in Punjab had been showing a bunch of papers to speaker Sumitra Mahajan to attract her attention. At one point, the speaker warned Mann and said his behaviour was "not good".
Mann had then moved to the other side of the Well and was standing near the Prime Minister's seat when the incident occured.
Congress chief Sonia Gandhi, who could not see what had happened as several of her party members were standing in the Well blocking her view, wanted to know what occured. She went into a peal of laughter after getting the details.
External Affairs Miniser Sushma Swaraj, seated in the front row along with the PM and other leaders, was also seen laughing.
While Mann and Sandhu Singh of the AAP, as also some Congress members, were raising slogans in the Well, another party member Dharmveer Gandhi was standing on his bench holding a placard demanding renaming of Chandigarh airport after freedom fighter Bhagat Singh.
A furious Kejriwal had yesterday accused the Modi government of targeting him over a day-long CBI raid at the Delhi Secretariat.
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