This smouldering night of separation) is an Indian Hindi song from the Bollywood film Lekin... (1990).
[1] The song fetched Lata Mangeshkar a national award (best female playback singer) and Gulzar a Filmfare award (best lyrics).
Neeraj Sharma in his book Gulzariyat - Gulzar's Songs: Discover What’s Beneath translated the first two lines of this song as: "The night of separation burns slowly like wet wood, neither complete ablaze nor wholly extinguished.
Lata Mangeshkar won her third National Film Award for Best Female Playback Singer in 1990 for this song.
[3] Gulzar won a Filmfare Award for Best Lyricist (1992).