Valmiki Ramayana Sundara Kanda Sarga 52 Shloka 2
Original Shlokaवधे तस्य समाज्ञप्ते रावणेन दुरात्मना। निवेदितवतो दौत्यं नानुमेने विभीषणः।।5.52.2।।
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दुरात्मना by the wicked self, रावणेन by Ravana, तस्य his, वधे killing, समाज्ञप्ते when ordered, विभीषणः Vibhishana, दौत्यम् message, निवेदितवतः who had declared (the purpose of his visit), नानुमेने did not approve.
Vibhishana did not approve of the killing of Hanuman, who had declared that he was an envoy (of Sri Rama) when the wicked Ravana ordered his murder.