Valmiki Ramayana Ayodhya Kanda Sarga 12 Shloka 49
Original Shlokaभरतेनात्मना चाहं शपे ते मनुजाधिप। यथा नान्येन तुष्येयमृते रामविवासनात्।।2.12.49।।
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मनुजाधिप O chief of men, भरतेन by Bharata, आत्मना च on my own life, ते to you, शपे I swear, यथा that, रामनिवासनात् ऋते except banishment of Rama (to forest), अन्येन by any other (means), न तुष्येयम् I will not be satisfied.
O king, I swear on Bharata and on my own life that nothing less than Rama's banishment will satisfy me.